How to prevent GRUB from appearing after selecting Ubuntu from Windows' Dual Boot menu?

Ok, I figured out my problem. Turns out I was clicking the "Write MBR" option every time I finished making changes in the GRUB Editor when all I had to do was click save so it did not overwrite the MBR but it did save my GRUB changes. Not sure what I did when editing the .cfg to make it overwrite the MBR but I'm sure it was my fault now, lol. Anyways, After using EasyBCD in Windows to add Ubuntu to the Dual Boot menu, clicking Write MBR, booting into Ubuntu and deselecting "look for other operating systems" and "show menu" in the general settings tab, and finally clicking Save (NOT Write MBR) I can avoid the GRUB menu when dual booting with Windows 7 and Ubuntu.


How to persistently maintain cloned mac address on Network Manager?

I find Gnome's NetworkManager frontend quite buggy if using some special configurations. You can always use nmcli (NetworkManager cli) to configure network profiles:

First, copy the network profile UUID you want to modify. You can list all UUIDs with (ignore $ symbol):

$ nmcli c

Next, use nmcli to configure the desired profile:

$ nmcli connection edit UUID_OF_THE_NETWORK_PROFILE
nmcli> set 802-3-ethernet.cloned-mac-address MAC_ADDRESS

Changing UUID and MAC_ADDRESS with the ones you want to use. Finally, save the profile with:

nmcli> save persistent
nmcli> quit


Desktop background goes crazy at startup

Try to go to Settings > Session and Startup > Splash and then test one of the several splashes available.


Is chroot the proper way to use packages from previous releases?

If you have software that requires use of an EOL (end of life) operating system, you should do your best to isolate it away from your primary system and quarantine it from the internet.
The best way to do this is to set up a virtual machine using VM software like VirtualBox.  Make sure that you disable the network adapter for the container.


gpu-manager is software that creates a xorg.conf for you.

It is a bug in gpu-manager: it recreates xorg.org on each boot. Let Ubuntu do its thing and disable gpu-manager as you already mentioned.

Have a look at /var/log/gpu-manager.log for any messages. If you add yourself to the bug below (that claims to be fixed but comments at the bottom disagree...) you need that log.

And this bug report has the work-around you describe (by Nash Kaminski on 2014-04-22):

  gpu-manager is responsible for overwriting your X config file. Commenting out the "start on" lines at the top of gpu-manager's upstart script located at /etc/init/gpu-manager.conf will temporarily disable gpu-manager and prevent xorg.conf from being changed.


Use clonezilla without booting from the clonezilla live cd?

Someone on the clonezilla forum told me what I needed:
https://sourceforge.net/projects/clonezilla/forums/forum/663168/topic/6559272

In the answer at the Clonezilla forum one recommendation was to just copy ocs-sr.

There is a deb file which can be used for the installation. Just go through the installation description.


Ubuntu Networking to Allow Connecting to Host Machine

This appears to be a problem with Unity itself. The networking is fine. Unity's Linux build is somehow not setting up its dependencies properly and preventing it from even trying the networking.


You could look in System Settings then Software Sources and in that there should be a tab for Additional Drivers. That's where I found the Broadcom driver for my Dell Studio


rmadison can't find libpython-dev, so it looks like it doesn't exist, maybe you're looking for python-dev?


If you hold down the 'super' key, which on my keyboard is the Windows key, for a second you can see a list of keyboard shortcuts pop up.

One of them is ctrl + super + D to minimize all open windows, i.e. to go to the desktop.

Due to the debate below, I feel compelled to amend my answer to note that on some systems, the shortcut may be ctrl + alt + D


Ubuntu 17.04 will not boot after installing on UEFI laptop

I had the same problem with a toshiba computer. after many attempts at reformatting and partitioning the drive. It turned out that the system requires a 1 GB recovery partition at the beginning of the internal drive.

my fix was to use the windows recovery CD's I had made to partition the disk.
don't install windows, just set disk up.then remove all partitions except the first.(it is usually flagged as hidden system, or hidden recovery).

then install ubuntu using the free space.


i've installed Firefox Developer Edition with Ubuntu Make but I don't find the icon

Umake put Firefox Developer into:

executable → ~/.local/share/umake/bin/firefox-developer
desktop-file → ~/.local/share/applications/firefox-developer.desktop


Wi-Fi not working with BCM43142 after upgrading to Ubuntu 18.04

Please edit /etc/network/interfaces

And remove the following content
iface wlp8s0 inet dhcp
address 192.168.1.241
netmask 255.255.255.0
gateway 192.168.1.1
braodcast 192.168.1.255
nameserver 8.8.8.8
Reboot


Create bash menu based on file list (map files to numbers)

To save the outputs of find in a bash array use this:

unset options i
while IFS= read -r -d $'\0' f; do
  options[i++]="$f"
done < <(find /dir/ -maxdepth 1 -type f -name "*.war" -print0 )

read reads the input from find null delimited (-d $'\0').

The array $options is filled with the filenames.

find searches only for files (-type f) within the given directory (-maxdepth 1) with ending .war (-name "*.war") and prints them delimted by the null character (-print0).

The select menu can be done like this:

select opt in "${options[@]}" "Stop the script"; do
  case $opt in
    *.war)
      echo "War file $opt selected"
      # processing
      ;;
    "Stop the script")
      echo "You chose to stop"
      break
      ;;
    *)
      echo "This is not a number"
      ;;
  esac
done

It works as follows:

1) /dir/old.war
2) /dir/debug.war
3) /dir/release.war
4) Stop the script
#? test
This is not a number
#? 2
War file /dir/debug.war selected
#? 4
You chose to stop


how to update python version on ubuntu 14.10

Ubuntu 14.10 comes with Python 2.7.8 (available as python, python2 and python2.7) and Python 3.4.2 (available as python3 and python3.4) installed by default.

As many programs depend on them you can't remove any of them without breaking your system.


Keyboard and mouse not recognized when installing 18.04.3

With much help from others more knowledgeable than I, the following solution was found.

First, in the BIOS settings, under the Peripherals tab, you must set "IOMMU Controller" option to "Enabled". Without this setting, USB will not work at all under Linux. My understanding is that the integrated NIC will not work either, but I had it set properly before I got that far (I used a GParted live CD for partitioning prior to installation). USB mice and keyboards still work fine in the BIOS settings, so no worries making this simple change.

Secondly, once Linux is installed USB 3.0 ports will not work (they don't fall back to 2.0 or anything, they are just dead) until you add GRUB_CMDLINE_LINUX="iommu=soft" to /etc/default/grub and then run update-grub (Debian) or grub2-mkconfig (Red Hat) to apply the change.

This was from a review of the Gigabyte motherboard by David A. Jayne. For more details, see his complete review at https://www.amazon.com/GIGABYTE-GA-990FXA-UD3-990FX-SATA-Motherboard/dp/B00545BZOG


Hej and welcome to Ask Ubuntu!
The overall market share of Ubuntu Server is about 9.3 percent and counting, popular sites using Ubuntu include Wikipedia, The Internet Archive, Buzzfeed and others.[1]
Ubuntu is and always will be free[2], the same goes for the server version.[3]
There are paid-for enterprise support options available[4], but the base product (Ubuntu itself and the bundled software) won't cost you a penny, even if you'd make millions of dollars using it.
There is free community support here on Ask Ubuntu and on the Ubuntu Forums, as well as the Official Ubuntu Documentation and the Community Help Wiki to help you with all Ubuntu related questions or problems, completely free of charge.
Further advantages of Ubuntu (and, to be fair, GNU/Linux in general) include Freedom (no restrictions, no vendor lock-in...), Security[5] and cost-efficiency (no license fees, free upgrades, lower maintenance cost).
Also, the included package management system (APT, Advanced Packaging Tool) and the many freely available administration tools make upgrading and deploying software as well as other maintenance tasks across many computers and company networks easy and painless.

Further reading

Frequently Asked Questions about the Ubuntu Server Edition
Server case studies | Ubuntu Insights
Ubuntu adoption case studies (for companies, associations, schools)

References

“Usage statistics and market share of Ubuntu for websites”, W3Techs, January 2014
“About Ubuntu”, Ubuntu.com
“Ubuntu Server - for scale-out computing”, Ubuntu.com
“Server Management”, Ubuntu.com
“Security/Features”, Ubuntu Wiki, May 2014


That usually happens when you try to manually set a setting which is currently controlled by some other automatic. Try toggling ''exposure_auto_priority'' to see if that looses the grip of the auto algorithm on that particular setting.

For me, for example, setting  ''white_balance_temperature_auto'' to 0 allowed me to manually set ''white_balance_temperature'' which resulted in "failed: Input/output error" before.


Can I hide running applications from the unity launcher?

I haven't tried it with Unity myself, but you should be able to use Devil's Pie to hide them.


Error copying images from camera using Nautilus

Looks like this is broken in all recent Gnome releases.

Debian: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=715436
Fedora 19: https://bugzilla.redhat.com/show_bug.cgi?id=984913
Arch Linux: https://bbs.archlinux.org/viewtopic.php?id=165497

The Arch thread has several workarounds, my favorite is using "gphoto2 -P":

Connect camera
Eject camera via Nautilus
Open a terminal, cd to the directory you want your photos to be placed, run "gphoto2 -P". It will download all the images to the current directory.

If you don't have gphoto2 installed: sudo apt-get install gphoto2


Libre Office Writer - how to add text to an image

Background Image

Insert image
Left click on "Insert" menu, and click on "Image". From the file selection window select an image.
Format image
Right click on the image, left click on "Format Image", In LO 5.4.1.2 click on "Properties..."
In the Wrap tab select "Through", and check "In background".

Results in any text/text box being printed over the background image.

Text Box

Insert text box
    Left click on "Insert" menu, and click on "Text Box". Using the mouse left click and drag to create a text box, type text into the box. The color of the text may need to be changed for visibility.


How to change screen resolution? i tried everything

The Workaround here should fix this issue: https://help.ubuntu.com/community/Unable%20to%20change%20Screen%20resolution%20in%20Ubuntu#Workaround


Does YouTube support 5.1 surround sound?

Apparently YouTube does not support true 5.1

5.1 support only means that Youtube gathers audio from the extra channels, then converts them into 2.0 output so the sounds are sent to all speakers.

HERE is a Stack Exchnage post I read about this


Drag and Drop Files in Unity with 3 Monitors

I had similar problems with a 3 monitor (2 NVidia GPUs) setup using 10.04 (x64) and was able to work around the issue by physically connecting my monitors in a different order to the cards.  Even though the nvidia-settings tool allowed me to change the order of the displays, I'd get strange problems if I varied the default order that shows up initially.

Hope this helps


Wireless keeps cutting out every several minutes on a Realtek RTL8187SE

Dropped WiFi connections can either be environmental or software related.

I'll try to keep this as generic as possible, so that the answer could apply to any WiFi cards.

Three environmental areas that you should consider before delving into the software suggestions below:

WIFI Encryption - Try changing the encryption method on your WIFI router, see if that results in a more stable connection.
WIFI Router itself - Try moving to a new access point, do you still have connectivity issues?
WIFI Channel - Try changing the channel your router is communicating on. In your area, there may be too much traffic on the channel you selected.

Once you've ruled these areas out, five software possible avenues you could consider:

Looking to see if any WiFi Backport exist and if so, installing the appropriate package
See if this is a 64bit vs 32bit issue
Trying a newer Kernel, either the next available stable kernel OR testing the very latest alpha/beta Ubuntu version which contains the latest release candidate kernel
Disabling the power management of your wireless card
(the choice of very last resort) using NDISWrapper

Backports

The kernel developers often release a software package containing updates for WiFi devices derived from the latest or most recent kernel.

For Natty, this package is called linux-backports-modules-cw-2.6.39-generic (thanks Jorge).  This package can be found either in the proposed repository or in the backport repository.  Tick the appropriate checkbox in Software Sources and Reload the latest updates.

Open either Software Center or Synaptic Manager and search for the package named (or similarly named) as above.  If the package is available, install the package, reboot and see if the WiFi connection is more stable.

64bit vs 32bit

As linux matures, 64bit vs 32bits issues should reduce.  However it is not unknown that a 64bit installation can be more unstable compared to a 32bit installation - and visa-versa.

For your card, I found a bug report for your Wireless card here that describes your symptoms - 64bit kernel, wifi drops connection randomly.

Take a backup of your system first using, for example, Clonezilla, so that you have something you can easily restore from.

Try installing the 32bit version of Natty.  See if your connection is more stable.  You could also test the other suggestions in this answer in this 32bit configuration.

Newer Kernel

Testing a newer Kernel can sometimes cause instability issues - for example boot and black-screen issues.  I would recommend you remove any Additional Hardware graphic drivers (e.g. ATI or Nvidia) first.  I also recommend that you have a good backup for example, using CloneZilla which you can restore from.

Look for the next stable mainline kernel from here on LaunchPad.

Looking at the change lists on kernel 2.6.39, it does mention some updates for your card.

You can install the 2.6.39 kernel as described in my answer here.

Disabling Power Management

Sometimes wireless cards can have Power Management modes.  Its not unknown for these modes to be buggy in linux.  Switching off power-management can sometimes help.

You may have to do some Google research to see if there is a specific method to disable Power Managment.  Below is a method I've used in the past for some cards.

From a terminal type:

gksu gedit /etc/pm/power.d/wireless

If the file opened contains any statements then add the following line (if it doesnt already exist)

/sbin/iwconfig wlan0 power off

If the file opened is empty then add the following

#!/bin/sh

/sbin/iwconfig wlan0 power off

Now copy and paste the following:

sudo chmod +x /etc/pm/power.d/wireless

Then reboot.

source

NDISWrapper

Note - NDISWrapper can cause black-screen issues on boot - so have a good backup for example, using CloneZilla which you can restore from.

NDISWrapper was at one time a few years ago, one frequently used method for wireless cards because the kernel had so few wireless driver support.

Its fallen out of favour in recent times for many reasons that I wont go into...

To be honest, RTL8187se has been in the kernel for some time so the following suggestion should be considered as a last resort.

Search for ndisgtk in the software center and install

Now download the windows xp drivers, in your case from Realtek

Extract from the zip file.

Using ndisgtk - navigate to the folder - RTL8187SE - WinXP and point ndisgtk to the .inf file.  Hopefully now (maybe after a reboot) network manager should use this driver in preference to the RTL8187SE kernel driver - n.b.  hopefully you dont have to blacklist the kernel.


Apple G4 733Mhz and 512Mb Ram... Any suggestions on what to use for good performance?

Xubuntu or Lubuntu might go good on this. Give a few live cds a try. I certainly know Ubuntu will run however it might not be very reactive. Stuff will still get done fast though you might spend some time waiting for firefox to come up. :)


How do I enter single user mode when dual-booting Mac OS X and Ubuntu?

I read somewhere on the internet that I have to set Mac OS X as the deafult OS in the yaboot.conf file and power down the iMac and hold whatever keys I need to hold on the keyboard and just wait until yaboot boots to Mac OS X by default. Just add defaultos=macosx to your yaboot.conf located in /etc/yaboot.conf. You can do that by starting the terminal and authenticating as root by typing "sudo su" and then typing "gedit /etc/yaboot.conf" which will open a text editor where you can add that line after the lines you have, but before the "image" line break. Typically you should add it after the "enablecdboot" line.

I haven't tried this yet as permissions on my iMac were totally screwed, but I think it should work!


I want to execute a terminal command using php?

Since php is not a compiled language, you can't execute it directly.  You must tell the system how to open it, just like a shell script.

With a shell script, you can run it using sh filename, or bash filename.    Another way is to write the script with a special comment line at the top, called a "sha-bang", or "crash-bang"; for a bash script, it's like this:
#!/bin/bash
You can then make the file executable, and execute it like a normal program.

You can do the same for php.  Either run it under php, if you have it (php xxx.php), or add the sha-bang, but make it say /bin/php rather than /bin/bash


Your PC failed to connect to repositories required to update. Was your Ethernet network cable attached?  If you use WiFi instead of Ethernet, had you selected a WiFi access point and passworded in successfully?

Then, in the last three lines, you tried to launch the gedit editor, which was not installed, and is not part of the basic installation. Perhaps you could use nano instead, which is part of the distro?


Screen dimming doesn't work (Ubuntu 14.04 LTS)

You have an outdated or incompatible proprietary driver for your card. Open the Additional Drivers program and check for new drivers. Select the newest one, apply and reboot.


How to create and submit package for Qt application

If it's a commercial application, just build a tarball containing everything needed to run it, and upload it to the myapps site. They'll help you through the rest.


You could spend a bunch of time trying to repair this, your best bet is to just reinstall over your existing installation and doublechecking that you don't format the partition.

You'll lose the packages you have installed and have to reinstall them, but it's much less work than reconstructing the permissions on your system.


You need to remap the key to Grave.

This is taken from this answer.

xev will output some information about the pressed key. The third line is important. It should look similar to:

state 0x10, keycode 49 (keysym 0xff55, Escape), same_screen YES,

in this example Escape is the name of the behaviour the key is assigned to at the moment, the number keycode is the internal id to recognize the key.
now when you want to change the keys use xmodmap.

 xmodmap -e "keycode 49 = grave"

This changes the key with keycode 49 on your keyboard to the key grave. It's pretty simple. Unfortunately, this loses the ~ char.

To allow the ~ key, you have to assign it to a modifier. The modifiers are, in order:

(no modifier key used is implied as first)
shift       Shift_L (0x32),  Shift_R (0x3e)
lock        Caps_Lock (0x42)
control     Control_L (0x25),  Control_R (0x69)
mod1        Alt_L (0x40),  Alt_R (0x6c),  Meta_L (0xcd)
mod2        Num_Lock (0x4d)
mod3
mod4        Super_L (0x85),  Super_R (0x86),  Super_L (0xce),  Hyper_L (0xcf)
mod5        ISO_Level3_Shift (0x5c),  Mode_switch (0xcb)

So we want it to be ` when there is no modifier (item 1) and ~ when there is a modifier. The command is:

xmodmap -e "keycode 49 = grave asciitilde"

asciitilde is the ~ key.

You can also set it to change with caps etc, so if I wanted | when caps is on, you use:

xmodmap -e "keycode 49 = grave asciitilde bar"

bar is the `| key.

Note: These change are for the active X session only and will be lost after reboot.
When you want to save the changes permanently you have to run the following commands after the ones above:

xmodmap -pke >~/.Xmodmap

(it creates a file named .Xmodmap in your home directory (~))

Then you have to create a file named .xinitrc in your home directory where you put command xmodmap .Xmodmap in.

source: Ubuntu Foruns


How do I get rhythmbox to play MPEG1 files?

Since you are trying to play an MPEG file, You can play it with installing gstreamer0.10-ffmpeg which is much smaller in size as compared to ubuntu-restricted-extras (with all it's dependencies, which is 67.0 MB in total size).
So you might want to install it without using the big metapackage (ubuntu-restricted-extras includes all codecs and flash).

Install it by clicking on the button:

Or open a terminal and use this command:

sudo apt-get install gstreamer0.10-ffmpeg

It is about 8,342 kB in size


The package that you installed is Nemo, that is a file manager (born as fork of Nautilus) and that is used in some Ubuntu flavours like Ubuntu Budgie. Also Linux Mint uses it.
I don't know which kind of dependencies brought you to install it, but you can remove it by: (flag suggested in a comment by @AkibAzmain)
sudo apt remove --autoremove nemo


By default, the 11.10 preloads do not make use of the Nvidia card, even though it may show up in lspci.  This is because of the poor optimus support (as others have already stated).  For all intents and purposes, treat the Nvidia chip as disabled.

The 11.10 preloads on these machines are set up to only use the Intel Graphics chip. You can configure the graphics settings by going to System Settings and then clicking Displays to adjust the resolution as well as set up multi-head monitors.


I am stuck on step 8 of Creating A USB boot Disk Mac Style

I tried dragging my .dmg from Finder into Terminal to get the exact path and avoid typos.

I suggest that there needs to be a space between the dmg and the of  shown in the following:

.dmg of=/dev (instead of  .dmgof=/dev shown above.)

And try typing disk1 instead of disk1s1.

Best of luck,
Phil


It just occurred to me that since you are trying to edit files in /var/www/html, all you need to do is add yourself to the www-data group and make some changes to director permissions

First:

 sudo adduser username www-data

Then change the directory owner and group

 sudo chown -R www-data:www-data /var/www/html

allow the group to write to the directory

 sudo chmod 775 /var/www/html

Now /var/www and any file or directory in it has group www-data permissions

Just log out and it again to make sure the group change takes effect

Then run from terminal

 groups username

And it will list groups you are a part of. You should see www-data. If so, go try and edit file and it will work.

Sorry this didn't occur to me first.

Edit: just to clarify, you added yourself to www-data and allowed read/write on /var/www to anyone within group www-data.

When you open chromium, it will be opened as your user, that has permissions to access the files your trying to edit


How to import contacts into thunderbird?

Click on Tools in the top bar and then open the Import menu

As type of material choice "Address Book" and click Next

As type of file choice "vCard file (*.vcf)" and click Next

Now search your file with the new window and open it.

If everything finished correctly, you will get a success message like this one and when you open the address book you will see your imported contacts there.


Urgently Need Help, Can't boot ubuntu after shutdown didn't properly. [Stuck in black screen]

If you boot the computer from Ubuntu CD (start live session, not installation process), you will then be able to mount your HDD. No data on the HDD will be erased just by starting live CD (it might have been damaged when you suffered power out though).


Based on your output can you try this command. You seem to be missing some required library. Try this command to install those missing libraries.

sudo apt install libgdk-pixbuf2.0-0 libgtk2.0-0 libxtst6


Insert your wireless adaptor and give it a moment to detect the hardware, then check the network icon on the taskbar to see if it has worked.  Failing that run the Software Sources and click on Additional Drivers to auto-detect any new drivers available for your hardware (you need to be connected to internet via lan cable for this to work).


AppArmor audit logs ... what does this mean?

First, it means that you should read man -k apparmor, and the man pages.

Second, the apparmor="STATUS" shows that this is a Status report, reporting on a "profile_replace" operation, replacing the current apparmor profile with the profile="unconfined" profile, on behalf of name="/usr/lib/cups/backend/cups-pdf" pid=31430, name="/usr/sbin/cupsd" pid=31430 and name="/usr/sbin/cupsd" pid=31430, using the apparmor_parser (see man apparmor_parser) command.

In English, the is CUPS - Common Unix Printing System telling AppArmor it wants to execute in the old, "unconfined", "AppArmor don't bother me", mode used by programs that have not adapted to life with AppArmor, yet.

For more information about AppArmor, see What Is AppArmor?" https://askubuntu.com/questions/236381/what-is-apparmor?rq=1

You do not need to be worried, but a certain level of concern is always appropriate.


Top Panel icons+text Ubuntu 20.04 have become extremely small

I don't know what causes it, but I found a solution.
I went into Gnome Tweaks panel (installed from Ubuntu Software) and changed the Font Size under Fonts to 1.01 and back to 1.00.  That fixed it.
If you aren't using Gnome Tweaks, you may be able to do it in Settings as well, but that worked for me.


How do I backup computer that wont let me go on windows from usb hard drive with ubuntu?

You will need an Ubuntu Desktop install image.  You will need to boot to this image instead of your hard drive and use Ubuntu to offload you files to another device like a USB drive.  Here are the steps:

Download the Ubuntu 16.04 Desktop image here.  You will need to create a bootable USB stick or burn it to a CD.
Insert your shiny new installer media and fire up your machine.  Chances are it will boot to your media automatically.  If not you need to determine what keystroke is needed to select a boot device.
Let the Ubuntu Live Installer boot up and select "Try Ubuntu" from the menu that pops up.
Connect the device that you want to copy your data to.  It should show up on the desktop as a hard drive icon.

Click on the file cabinet on the left hand side.  You should see 3 drive entries.

Mine is a VM and doesn't have any additional drives attached,  but it should look like that image.  Yours will have 3 drives listed instead of just one:

Computer:  The live Ubuntu OS that you are looking at.
USB Drive:  The drive you want to copy your files to.
Windows Drive:  Your broken install that you want to copy from.

Open your Windows drive by double clicking on it, select the files you need to keep, right click and select copy, Right click on your USB Drive and select paste.  You files should start moving over to the USB drive.

Once your files are copied over, go ahead and close those windows, double click the "Install Ubuntu 16.04 LTS" icon and follow the instructions to install Ubuntu.  Try it.  You'll like it.  Here is the official installation guide.

You are already a member of the community, so if you get stuck just come back here and ask a question again.

Now you can put your files wherever you want to.

:)


Stuck on 800x600 resolution on Ubuntu 14.04LTS with GeForce GTX 750 Ti

You might try moving/backing up your xorg.conf, or monitors.xml files to see if a rebuild corrects them. There are quite a few changes to X and the desktop environment between the long-term releases.

mv ~/.config/monitors.xml ~/.config/monitors.xml.old
sudo mv /etc/X11/xorg.conf /etc/X11/xorg.old

Additionally, if that doesn't work - try making sure your nvidia drivers are above 334 (the version where the GTX 750 was supported). The oldest "stable" release related to the card is the 340 version. 352 is pretty common as well, and 361 is cutting edge. The graphics repoistory ppa has 367 in it, which I wouldn't recommend.

Press CTRL+ALT+F1 to drop to a console.
sudo service lightdm stop
sudo apt-get purge nvidia*
sudo apt-get install nvidia-340
If your motherboard has onboard intel graphics additionally install nvidia-prime (That's the package name)
sudo shutdown -r now

You may also want to look into blacklisting nouveau. A google search will tell you how to do that.


Is it possible to mount an iso in writable mode ?

Unfortunately, no.

Avinash-Raj said here, [flagged as dupe]

  ISO files are always mounted as read only. So copy files from the
  mounted ISO to another folder and then make changes you want. You can
  then use mkisofs to generate a new ISO from the modified folder.


When I type "gur" or "fro" quickly Ubuntu brings up the search window. How do I turn that feature off?

"Updated Answer for Ubuntu 16.04"
To Disable the "HUD" Key, Open System Settings and Click On Keyboard....

Then Shortcuts....

Click on "Key to Show HUD" and hit [BACKSPACE] to Disable.


Black Screen (but with cursor) after wake-up from suspend to RAM

I have the same problem as you and used to have a similar problem on previous versions (< 12.04). My solution used to be to go tty1 by pressing Ctrl+Alt+F1 and then killing the gnome-screensaver program. Things would go back to normal.

This has not worked for me in 12.04, but maybe it might work for you. In 12.04, all I can do is killall -u myusername to close my session and then I have to log back in just to avoid having to reboot.


How to verify if a reboot was due to power outage?

The last command will display crash for the end time of a session if the shutdown was not clean, which would include a power outage.  Example entry:

myuser pts/1        myhostname  Wed Sep 28 14:18 - crash  (00:23)

Looking at your last entries (assuming this is all of them) there are no crashes listed there, so no power outage occurred while this system was on.  The reboot that is listed here looks to be a commanded reboot and not a crash.  If you didn't manually reboot this box, you then a program with root access did.


Disabled booting from hard drive in bios

In order to re-enable booting from hard drive do the following:
Turn off your computer.
Turn on and start pressing the key to enter bios (you will find it in your computer's manual or on the manufacturer's website. In my case it's DEL).
Go to booting options and re-enable hard drive in the bios.
Reboot.


can't boot into ubuntu please help my files are all gone

try pressing shift right after the bios and see if you can get a boot menu. If you really need your files back but know you can't boot into ubuntu, boot the livecd and copy the files from the filesystem to a usb


Type this command in terminal (press ctrl+alt+t to open)

sudo apt-get install ubuntu-restricted-extras

It will install all media codecs which are necessary for playing media files.


What would happen if my power trips while I'm installing Ubuntu?

Your installation might become corrupt but you can repair it with a live CD or USB.
For documentation how to repair it, please search askubuntu as I have seen it here.


How to download GNASH SWF Player from Ubuntu Centre to Synaptic Manager?

Search for this in the Ubuntu Software Center application and click install. It will be installed in your computer.


Help in correcting or bypassing a bug resulting shifted screen in my ubuntu

This is Ubuntu, this is not Windows: newer is not always better: I'm running on nvidia-352 and am very happy with everything.
If the 352 series works flawlessly, keep using that one and skip 355.  If some day 365 comes out, try that one and if it gives you better performance, also use it but if you get worse performance/features/... just roll back!
(Oh and I'm on 14.04 LTS too, because I like stable and working applications, kernels and drivers...)
;-)


Ok, this was not a first for me, after all. I ran across some old notes I made last time this happened. Here's how I fixed it.

What percentage of the boot partition is used?

df -H | grep boot
/dev/sda2    240M  224M  3.5M  99% /boot

What kernel images are currently installed:

sudo dpkg --list | grep linux-image
ii  linux-image-3.8.0-29-generic         3.8.0-29.42~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-34-generic         3.8.0-34.49~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-35-generic         3.8.0-35.52~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-36-generic         3.8.0-36.52~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-37-generic         3.8.0-37.53~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-38-generic         3.8.0-38.56~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-39-generic         3.8.0-39.58~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
ii  linux-image-3.8.0-41-generic         3.8.0-41.60~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
iF  linux-image-3.8.0-42-generic         3.8.0-42.62~precise1                    Linux kernel image for version 3.8.0 on 64 bit x86 SMP
iU  linux-image-generic-lts-raring       3.8.0.42.42                             Generic Linux kernel image

Which kernel image is actually being used:

uname -a
Linux backup 3.8.0-41-generic #60~precise1-Ubuntu SMP Fri May 16 00:18:00 UTC 2014 x86_64 x86_64 x86_64 GNU/Linu

Remove each old kernel not being used:

sudo apt-get purge linux-image-3.8.0-29-generic linux-image-3.8.0-34-generic linux-image-3.8.0-35-generic linux-image-3.8.0-35-generic linux-image-3.8.0-35-generic linux-image-3.8.0-36-generic linux-image-3.8.0-37-generic linux-image-3.8.0-38-generic linux-image-3.8.0-39-generic

After this I was able to upgrade:

sudo apt-get upgrade


Readers who want a quick answer please skip to the last paragraph of this answer.

There's not much difference between Nvidia drivers in the upgrade direction. The later version of the Nvidia driver will usually have a little bit better performance, but you can use either version and either of the versions will work, however there can be a real difference between the two Nvidia drivers in the downgrade direction. Sometimes the older Nvidia driver will not work at all with your GPU because it's not compatible with it. If that little performance boost doesn't matter to you, then stay with the older driver version that is known to work and you won't have any problems.

That explains upgrading vs. downgrading Nvidia drivers, but there is the additional matter of getting the Nvidia driver version right the first time, so you don't need to either upgrade or downgrade it. Ubuntu has a built-in ubuntu-drivers program that can decide automatically which graphics driver to install, and streamlines the installation of Nvidia drivers. Open the terminal and type:

sudo ubuntu-drivers autoinstall
sudo reboot

The autoinstall command of ubuntu-drivers installs drivers that are appropriate for automatic installation including their dependencies.

The devices command of ubuntu-drivers lists proprietary drivers that are compatible with your computer's GPU. If your computer has an Intel processor and it doesn't have a discrete graphics processor, the command ubuntu-drivers devices will not return results that show that a proprietary graphics card driver is available to be installed because the Intel graphics driver is built-in in Ubuntu.

If you visit the official NVIDIA website you will often see that the latest version of the proprietary graphics driver for your GPU is a little bit more up-to-date than the version of the same graphics driver that is available from the default Ubuntu repositories. Don't worry about this, because if the difference between version numbers of the two proprietary graphics drivers is small, then you will get similar performance by using either of the two drivers.

If you are currently using the nvidia-driver-435 proprietary graphics driver, I don't think there would be much benefit in upgrading it from version 435 to version 440, compared to the advantage of staying with nvidia-driver-435 from the default Ubuntu repositories. If you install a graphics driver from the default Ubuntu repositories, you will also get automatic updates for that driver which are sometimes linked to kernel updates.


"Left Ctrl to first layout; Right Ctrl to last layout" breaks Copy/Paste shortcuts

Yes,there is.In the gnome tweak

Keyboard & Mouse > Additonal Layout Option > Switching to another layout


How can I install Emerald Theme Manager, and switch between Emerald and Metacity themes?

Another solution is to install emerald version 0.9.5 via PPA :

sudo add-apt-repository ppa:nilarimogard/webupd8
sudo apt-get update
sudo apt-get install emerald

After installation, press Alt+F2 and type emerald --replace.
And if u want to get back to gtk themes press Alt+F2 and type gtk-window-decorator --replace.

source:
        here


BURG bootloader is old and unmaintained, and may or may not work with new Ubuntu releases even if you succeed at installing it. I suggest you apply a theme to Grub2 if you want a nicer GUI, or try a modern graphical bootloader like rEFInd which promises to work on UEFI-based machines with different operating systems.

sudo apt-add-repository ppa:rodsmith/refind
sudo apt update
sudo apt install refind

Warning: The method stated below is completely not recommended.

If you, for some reason, insist on using BURG you can manually edit its repository:

sudo nano /etc/apt/sources.list.d/n-muench-ubuntu-burg-bionic.list

and replace artful with xenial

deb http://ppa.launchpad.net/n-muench/burg/ubuntu xenial main
# deb-src http://ppa.launchpad.net/n-muench/burg/ubuntu xenial main

and finally enter sudo apt update && sudo apt install burg to install burg.


After changing to Oracle Java on Netbeans bottom of text is now cut off Ubuntu 16.04

I fixed the issue by changing NetBeans settings.

GoTo: Tools -> Option -> Appearance -> Look and Feel and select "Preferred Look and Feel" = Metal (was GTK+ by default) and check "Maximaze use of native look and feel".

Then restart IDE and all menus were OK. Play with IDEs settings there to see what works for you.


I need to load driver for Epson Perfection 4180 Scanner

None of those will work. They are only offering Fedora/RedHat drivers and tar.gx binaries. Thus you are not provided a driver you can install correctly from that website.

Please direct your complaints to Epson for the disgraceful way they are treating Ubuntu users by not providing drivers.


Set up Shutter (or other screengrab tool) to capture a preset area from a keyboard shortcut

Shutter
When calling Shutter from the command line we can give it option --select to grab a defined region of our screen with:
shutter --select=x,y,width,height

Below command will save the screen from coordinates 0,120 with image dimensions 800x600 to the file screenhot.png in the directory we are in.
shutter --select=0,120,800,600 -e --output="screenshot.png"

For convenience we can add this command to a keyboard shortcut.

ImageMagick Import
Another very versatile application to obtain custom screenshots would be import of ImageMagick .
import -window <id|name> [-crop <geometry>] filename.png

We can import either from the whole desktop (-window root) or from a window defined by ID or name (run xwininfo to get the window ID on mouse click). The <geometry> value defines the screen region with the following syntax: <xsize>x<ysize>+<xoffset>+<yoffset>. Below command will save a 800x600 pixel sized screenshot with offset x=0,y=120 off the left upper corner:
import -window root -crop 800x600+0+120 testshot.png


14.04 - gnome terminal missing after installing virtualbox

So after running the two commands that @steeldriver suggested, I realised that I'd somehow managed to totally uninstall the gnome terminal from my laptop.

sudo apt-get install gnome-terminal

solved this problem for me.


Can't upgrade from Ubuntu 13.04 to 13.10

Most times it's because of the last point listed: You've got some PPA's enabled which can't be upgraded.

Disable all PPA's you've installed manually and run the upgrade. After upgrading, re-enable them.

This is most easily done via the "Software & Updates" utility.


Please open a terminal and run:

lspci -nn | grep 0280

Is your device this? 14E4:4329 If so, it is a Broadcom wireless device. Please open Software and Updates and make sure that main, universe, restricted and multiverse are enabled. A window will open asking you to reload; accept and continue.

With a temporary working internet connection, open a terminal and do:

sudo apt-get install bcmwl-kernel-source
sudo modprobe wl

Your wireless should be working.

If your device ID is different, edit your question to include it and I will propose a solution.


/bin/sh is a symbolic link that doesn't point to /bin/bash

You were almost there with your ln command - except you probably needed to include the -f flag ('force') in order to overwrite the old link - also it's preferable to use a relative path for the target

sudo ln -sf bash /bin/sh

When you're done with the install, you can revert to the system default with

sudo ln -sf dash /bin/sh

There should be no need to change the script file 'shebangs'


How can I simply change into a text mode runlevel under systemd?

If you just need to switch to text mode with no GUI stuff like the X server running, you can use systemctl to get your machine to the so-called multi-user.target:

sudo systemctl start multi-user.target

You revert this and get back to the desktop (graphical.target) by either rebooting or by switching back manually in the same way as above:

sudo systemctl start graphical.target

If you really need a true runlevel change to 3, that can be done using the init command, as @terdon pointed out in his comment:

sudo init 3

You can verify your current runlevel with the runlevel command. It will output two letters: the left one is your previous runlevel, whereas the right one represents your current runlevel.

You go back to the desktop by setting the runlevel to 5 again:

sudo init 5

Important general notes for both methods:

Both switching to multi-user.target or runlevel 3 will terminate the X server and kill all GUI applications and your desktop environment. Make sure you closed all sensible applications and saved your work before you start, otherwise their state will be lost!
Neither systemctrl start ???.target nor init ? do switch your active TTY. That means, if you run these commands from a terminal emulator on your desktop (normally on TTY7), you will be at a black screen afterwards (optionally with some debug output).

It's simply because the TTYs 8-12 are not connected to text consoles but reserved for video consoles to display GUIs. Only TTY 1-7 are text consoles.

So to operate in multi-user.target or on runlevel 3, you have to switch to a text console TTY, e.g. by pressing Ctrl+Alt+F1 for TTY1. You get back to the desktop (TTY7) later after you returned to graphical.target or runlevel 5 by pressing Ctrl+Alt+F7 respectively.

When you get to such a text console, note that you have to log in again first by typing your username and password as requested.


Hold shift during boot, then hit e to edit the GRUB entry.  Remove the part that says "quiet splash" and replace it with "text" to see what's happening during boot.


Infinality problem with fonts in firefox

Solved. Problem was with some ttf fonts, installed manually. So just removed it and reinstall ttf-mscorefonts-installer.


Is there an kernel version list available somewhere?

I think the question itself is somewhat invalid, since you can compile any custom Linux kernel and use it with Ubuntu. For example, I'm renting a VPS running Saucy (13.10), which comes with the 3.11.x kernel by default, but my provider is using 2.6.32 so it's actually running on 2.6.32.

Anyway, Wikipedia has a list of the default kernels shipped with each version of Ubuntu.


Is there a way to check Ubuntu installation health?

If you do a

sudo apt-get update

you will be warned about problems if there are any related to packages. That solves these 2:

All packages are healthy.
There is no broken package

That command will install all updates for your installed software. I assume "healthy" means as up to date as possible. If there are broken packages you will get warned about them as soon as those are checked.

Regarding ...

If there is a missing necessary package or not.
There is no missing file in system.

How would a system be able to tell you if a file is missing? In general a program will throw some sort of error when it needs it during execution of that software. Something like  "segmentation fault" or a python error. If there are none you should assume all if fine.

If you would want a list of all the files missing you would need to start every application on your system. Undoable even automated.


I know you can run some Windows programs from Ubuntu using Wine. If you want to run the Windows operating system, however, I think you would have to use GRUB unless you want to run it virtually. Luckily, if you install Windows first and then install Ubuntu, Ubuntu will be the first option on the GRUB menu followed by safe mode and the recovery console and then Windows. So, if no key is pressed on boot up, Ubuntu will be your active operating system.


Why do I no longer receive any security updates?

sudo apt-get update
sudo apt-get upgrade

should show you enough of the noise to reassure you.


Switching between virtual console and GUI

By default Ubuntu has 6 virtual consoles tty1-tty6 which are accessed by the keyboard combinations Ctrl+Alt+F1 to Ctrl+Alt+F6. The virtual console can also be accessed from a black screen if the boot process stops at a black screen when booting. To access the GUI from any virtual console press the keyboard combination Ctrl+Alt+F7.

Starting with Ubuntu 17.10 the virtual consoles are accessed by the keyboard combinations Ctrl+Alt+F3 to Ctrl+Alt+F6. To access the GUI from any virtual console press the keyboard combination Ctrl+Alt+F2.

To login from a virtual console:

At the login: prompt type your username and press Enter.
At the Password: prompt type your user password and press Enter. After you have logged in, you can run commands from the virtual console.
To bring up the normal Ubuntu login screen run this command:

sudo systemctl start lightdm.service

In 16.04 and later run this command instead to bring up the normal Ubuntu login screen:

sudo systemctl start graphical.target


unable to install Ubuntu12.10 on DELL inspiron 14z Ultrabook?

What partitioning method are you using during the install? Install alongside Windows or Something Else.

If your using Something Else you need to set up the partitions like this:

Ext4 filesystem mounted as /. This will be your root directory. (15-20 GB should be plenty.)
Ext4 filesystem mounted as /home. This will be your home directory where all your documents, pictures, music etc. will be installed.
swap area filesystem for the Swap partition (Once you select swap area the mount point option will be grayed out). (1GB should be more than enough seeing as the laptop has 6GB of RAM by default.


Instant Messenger for Ubuntu and Windows

Pidgin works well on both

  Pidgin is an easy to use and free chat client used by millions.
  Connect to AIM, MSN, Yahoo, and more chat networks all at once.

  Supported chat networks:

  AIM
  Google Talk
  IRC
  MySpaceIM
  Sametime
  Zephyr
  Yahoo!

  Find More Here

Screenshot from Run Skype as a daemon and manage it from Empathy or Pidgin in Ubuntu 11.04


How to turn on ubuntu pc with remote desktop

Powered off → unreachable.

You'll only be able to connect to your PC whenever it's on, because if it's off, then there's nothing running on the machine to contact to and there's no network active. A device in a powered off state is really off, you see. Similarly - your can't receive phone calls on your mobile phone without it having turned on. Some software can't do magic here.

However, I know of two techniques exist to manage the power without the machine being turned on, although it needs the wall socket power to be connected of course.

Wake on LAN. It's a feature of your network card - it will listen to "magic packets" to arrive on the interface to trigger a "power on" event on the PCI bus. It needs some standby power and another device in the same local network to be able to send such magic packets. So, basically, you'll have to

configure your BIOS to listed to WoL events.
have a network card that supports this.
configure your network card to do so (see manpage of ethtool).
have some device connected to the internet fire up the PC by sending the magic packet on the local network.

Major limitation: no available directly over the internet.

See also:

Wake-on-lan under Ubuntu 12.04
How can I enable wake-on-lan permanently?
Power Management - Sleep / Wake up Server when accessed

Out of Band management module. Some motherboards, mostly server and business-line desktop machines feature the Intel vPro with AMT. In servers you'll notice most have a dedicated card for this - HP iLO, Dell iDRAC, etc. With such a module you'll be able to control power (and usually more). See the manual of your desktop if you have it and how that works.

Major limitation: hardware requirements.

After the machine has been powered on with one of the techniques above, you'll have to make sure your remote desktop server (e.g. VNC server, NX server, etc.) is started and the network is automatically connected properly, so you can connect to it.


Chromium giving me "bus error (core dumped)" after recovering from corrupted filesystem using fsck

Okay, I fixed it by running

rm ~/.cache/chromium
rm ~/.config/chromium

and then restarting chromium


Apt update error - "An error occurred during the signature verification" (Chrome)

Apparently Google changed key for Chrome Linux repo. You can fix it by importing new repo key from Google:

wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

Now you should be able to update the system without any errors.

This works for APT-based distros: Debian, Ubuntu and derivatives (Linux Mint, Kubuntu, Xubuntu, Lubuntu, etc.)

For more info and a fix for RPM-based systems (Fedora, CentOS, openSUSE, etc.) see official Google Linux repositories page.


ALT+F4 combination should close the app and display the XFCE desktop.


Delete oldest file in a directory, when there are more than 7 files?

Introduction

Lets review the problem: the task is to check if number of files in particular directory is over certain number, and delete the oldest file among those. At first it may seem that we need to traverse the directory tree once counting files, then traverse it again to find last modification time of all files, sort them, and extract the oldest for deletion. But considering that in this particular case OP mentioned deleting files if and only if the number of files is above 7, it suggests that we can simply get list of all files with their timestamps once, and store them into a variable.

Problem with this approach is the danger associated with filenames. As has been mentioned in the comments, it's never recommended to parse ls command, since output can contain special characters and break a script. But , as some of you may know, in Unix-like systems (and Ubuntu as well), each file has inode number associated with it. Thus creating a list of entries with timestamps (in seconds for easy numeric sorting) plus inode number separated by newline will guarantee we safely parse the filenames. Deleting the oldest filename can also be done that way.

The script presented below does exactly as described above.

Script

Important: Please read the comments, especially in delete_oldest function.

#!/bin/bash
# Uncomment line below for debugging
#set -xv
delete_oldest(){
     # reads a line from stdin, extracts file inode number
     # and deletes file to which inode belongs
     # !!! VERY IMPORTANT !!!
     # The actual command to delete file is commented out.
     # Once you verify correct execution, feel free to remove
     # leading # to uncomment it
     read timestamp file_inode
     find "$directory" -type f -inum "$file_inode"  -printf "Deleted %f\n"
     # find "$directory" -type f -inum "$file_inode"  -printf "Deleted %f\n"  -delete
}

get_files(){
    # Wrapper function around get files. Ensures we're working
    # with files and only on one specific level of directory tree
    find "$directory" -maxdepth 1 -type f  -printf "%Ts\t%i\n"
}

filecount_above_limit(){
    # This function counts number of files obtained
    # by get_files function. Returns true if file
    # count is greater than what user specified as max
    # value
    num_files=$(wc -l <<< "$file_inodes"  )
    if [ $num_files -gt "$max_files" ];
    then
        return 0
    else
        return 1
    fi
}

exit_error(){
    # Print error string and quit
    printf ">>> Error: %s\n"  "$1" > /dev/stderr
    exit 1
}

main(){
    # Entry point of the program.
    local directory=$2
    local max_files=$1

    # If directory is not given
    if [ "x$directory" == "x"  ]; then
        directory="."
    fi

    # check arguments for errors
    [ $# -lt 1  ] && exit_error "Must at least have max number of files"
    printf "%d" $max_files &>/dev/null || exit_error "Argument 1 not numeric"
    readlink -e "$directory" || exit_error "Argument 2, path doesn't exist"

    # This is where actual work is being done
    # We traverse directory once, store files into variable.
    # If number of lines (representing file count) in that variable
    # is above max value, we sort numerically the inodes and pass them
    # to delete_oldest, which removes topmost entry from the sorted list
    # of lines.
    local file_inodes=$(get_files)
    if filecount_above_limit
    then
        printf  "@@@ File count in %s is above %d." "$directory" $max_files
        printf "Will delete oldest\n"
        sort -k1 -n <<< "$file_inodes" | delete_oldest
    else
        printf "@@@ File count in %s is below %d."  "$directory" $max_files
        printf "Exiting normally"
    fi
}

main "$@"

Usage examples

$ ./delete_oldest.sh 7 ~/bin/testdir
/home/xieerqi/bin/testdir
@@@ File count in /home/xieerqi/bin/testdir is below 7.Exiting normally
$ ./delete_oldest.sh 7 ~/bin
/home/xieerqi/bin
@@@ File count in /home/xieerqi/bin is above 7.Will delete oldest
Deleted typescript

Additional discussion

This is probably scary. . .and lengthy . . .and looks like it does far too much. And it might be. In fact, everything can be shoved onto a single line of command-line (a very much modified version of muru's suggestion posted in chat which deals with filenames. echo is used instead of rm for demonstration purposes):

find /home/xieerqi/bin/testdir/ -maxdepth 1 -type f -printf "%T@ %p\0" | sort -nz | { f=$(awk  'BEGIN{RS=" "}NR==2{print;next}'  ); echo "$f" ; }

However, I've several things I don't like about this:

it deletes oldest file unconditionally, without checking number of files in the directory
it deals with filenames directly (which required me to use awkward awk command, which will probably break with filenames that have spaces)
too much plumbing (too many pipes)

So, while my script looks horribly gigantic for the simple task, it does whole lot more checks and aims to solve issue with complex filenames. It probably would be shorter and more idiomatic to implement in Perl or Python ( which I absolutely can do, I just happened to choose bash for this question ).


ubuntu 15.04 alongside windows 10 dual boot

You could boot with a Ubuntu Live CD, open a Terminal and execute:

sudo grub-install HARDDRIVE
sudo update-grub

where HARDDRIVE could be /dev/sda.


What format does evolution store its mail in?

The default local folder implementation (for folders under "On This Computer") uses mbox(5) format, in which all the messages at the top level of each folder are kept contiguously in a single file, supplemented by some summary and index files. This structure lives under ~/.evolution/mail/local/. For every mail folder foo, some or all of the following files exist:

foo
foo.cmeta
foo.ev-summary
foo.ev-summary-meta
foo.ibex.index
foo.ibex.index.data
foo.sbd

The file foo is just plain old mbox(5) format and you may access it (carefully, and preferably read-only) with a MUA which understands mbox format, i.e. nearly all of them. For example with 'mutt':

$ mutt -R -f ~/.evolution/mail/local/foo

You should only do this when Evolution itself is not running. Note that any of the supplementary files can be removed and Evolution will reconstruct them next time it runs. You can also grep the file for text strings or addresses for use in the normal UNIX world.

The foo file contains only messages. If the foo folder contains other folders the contents of the foo.sbd directory recursively look like the above list.

I can honestly say with out any hesitation that I have got this answer from think FAQ-Evolution web-page. you can review that for more information.


The cmake command is needed to build that code, and you don't have it. This, rather than the [: -a: unexpected operator message, appears to be what is actually keeping your build from continuing. So first install cmake. Some software needs a very new version of cmake to build (which you can install if you need to) but most does not. I recommend you install the cmake package.

While you're at it, it's a good idea to make sure you have the usual toolchain for building programs on your Ubuntu system, too, which the build-essential package will get you.

These commands will install both cmake and those other tools:

sudo apt update
sudo apt install build-essential cmake

This will likely be sufficient to enable you to successfully build the software, or at least to get past the current error you're facing. However, I recommend you delete the build directory and its contents before proceeding:

rm -r build

After further troubleshooting steps that involve installing or removing software or editing files from the source code (or, if you like, even every time you build the source code), I recommend removing the build directory and starting fresh.

The messages you're getting about -a are probably not stopping the build from succeeding. You can probably ignore them. They also would likely go away if you used bash instead of sh, though I don't think that's the best solution. If you want to get rid of them or you suspect they are causing a problem then you can either edit the install.sh script to use the appropriate test (or no test) or you can manually perform the actions that script performs. So if you want to do something about this, see below for the details.

In the source code for both applet-window-buttons and applet-window-appmenu, install.sh currently has this as its complete contents:

if ! [ -a build ] ; then
    mkdir build
fi
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr .. -Wnodev
make
sudo make install

This is the file you are attempting to run with sh that is producing errors. Its use of the -a test is very strange. -a typically appears between two other expressions, and causes [ to return true when both expressions are true.

In Ubuntu, sh is provided by dash. If you use bash instead of dash, it may work (or appear to work). Perhaps that's what the authors did. However, instead of doing that, I recommend you either fix the script or just manually do what it does.

If you want to fix the script, one way would be to replace -a with -e or -d. The -e test takes a filename operand and checks if it exists; -d checks if it exists and is a directory. Another way to fix the script would just be to remove the if and fi lines entirely; mkdir would fail if the directory exists, but that's no problem.

mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr .. -Wnodev
make
sudo make install

But all this script does is create a build directory if there isn't one, change into it with cd, run cmake with some arguments, run make, and then run sudo make install. You can just do these things yourself. One way to do so is to run those commands in your interactive shell, one after another.

This has advantages. As written, the script doesn't stop just because some step reports failure, but you probably would want to stop. You could make further modifications to the script to achieve that (perhaps ending each line except the first and last with &&) but it's probably easier to just run the commands yourself if you're not planning on compiling the code numerous times.


Sometimes all of my directories are locked and I have to restart to fix it, I wonder why?

I recommend you to use "mount" command in console and look for / if it is mounted as ro (readonly) or rw (readwrite).

If it is mounted as ro, please check /var/log/syslog (you can use tail or less) for disk errors. Normally root partition is remounted on errors as read only - so that probably means your hard drive has failure or your filesystem is corrupted.

I recommend you to run this command as root (when filesystem is read-write) "touch /forcefsck" and reboot your system. This will force file system check and might solve your issue.


How can I calibrate my Xbox360 controller in Ubuntu 12.10?

Hopefully you've found the answer by now, but if not...

using jstest-gtk you need to hit the mapping tool and move ABS_Z to right above ABS_RZ.
To get this to set itself when you plug it in:

sudo jscal-store /dev/input/js0
(replace js0 with your joystick, you can see which it is in jstest-gtk)

you'll need the joystick package installed for this.


Do you use PPAs? Try to deactivate them in Software Sources > Other Software tab, and do sudo apt-get update in a terminal.


Are HP laptops generally incompatible with linux?

There is a list of Ubuntu-certified machines: For HP and 18.04, the list is here (which a somewhat smaller list than what you can find for Dell and Lenovo).

This doesn't mean that other HP machines won't work, though, if they use standard chips.


how can i open the files in /etc/NetworkManager/system-connections?

The files in /etc/NetworkManager/system-connections/ are simple text files and you can view them using cat or edit them with any text editor. But you must use sudo or administrator password to do so.

To open a file tt in that folder, I'd use this command

sudo -i gedit /etc/NetworkManager/system-connections/tt


Ubuntu One client not showing correct Usage

The quota being misreported should not be an issue in newer installs; it's entirely possible you have a lot more content synced from for example your phone or your tablet than you are aware of, if you have enabled automatic syncing from any of those devices. Failing that, please do get in touch with support as suggested.


If I send an email to my own server, does it pass through ISP?

Emails to local mailboxes SHOULD NOT go via your ISP with proper configuration
BUT number of sub-optimal and botched configurations is incredible e.g. some admins want internal mails to undergo anty-virus scans provided by their ISP disregarding privacy concerns.

Send email to yourself from the host and inspect Received: headers in the received message to check delivery path.


awk '/(^| )two( |$)/' ...

The (..) groups there are trying to ensure we're only matching "two". At the front it either needs to be the beginning of the line or a space and at the end it needs to be a space or the end of the line. In short, we're making sure the field equals two.

Hmm apparently you can also use word-boundary tags (which looks slightly more elegant but isn't as portable):

awk '/\<two\>' ...

Not sure what your specific use-case is (I assume it's not numbers), you might be just as well off with grep -E '\<two\>' ... but awk will give you a bit more flexibility if you need to do other stuff.


How to enter an account directly at start up

The default logins depends on your Display Manager. You can know which one you use by using this command:

# cat /etc/X11/default-display-manager

Then, you need to edit the configuration file of your display manager: gdm.conf or kdmrc or ... There is a comment part which explains how to use  the autologin.

On my ubuntu, I see a comment in the file /etc/gdm3/custom.conf :

# Enabling automatic login
#  AutomaticLoginEnable = true
#  AutomaticLogin = user1

I just have to uncomment to enable it.


does a remote process continue if initiated from my local? What are the rules on this?

No, it does not continue. Once your connection to the serverA is closed, the system terminates your shell and all processes running under them including scp. The rationale behind this is hygiene. You don't want to have running processes on your server, which do not belong to any active user.

You can prevent this behavior using screen, tmux or simply nohup, as described in many other questions.


Does the version of Opencv shipped with 12.04 support v4l2?

It does not! You have to build OpenCV with v4l support yourself.

Here is a guide
And another one (also see the 1st comment; seems someone made a script for a lot of things including this).
And another one

Script (save it as opencv2_4_5.sh, make it executable and run it) (includes v4l somewhere in the middle)(other versions are available on that site).

arch=$(uname -m)
if [ "$arch" == "i686" -o "$arch" == "i386" -o "$arch" == "i486" -o "$arch" == "i586" ]; then
flag=1
else
flag=0
fi
echo "Installing OpenCV 2.4.5"
mkdir OpenCV
cd OpenCV
echo "Removing any pre-installed ffmpeg and x264"
sudo apt-get -y remove ffmpeg x264 libx264-dev
echo "Installing Dependenices"
sudo apt-get -y install libopencv-dev
sudo apt-get -y install build-essential checkinstall cmake pkg-config yasm
sudo apt-get -y install libtiff4-dev libjpeg-dev libjasper-dev
sudo apt-get -y install libavcodec-dev libavformat-dev libswscale-dev libdc1394-22-dev libxine-dev libgstreamer0.10-dev libgstreamer-plugins-base0.10-dev libv4l-dev
sudo apt-get -y install python-dev python-numpy
sudo apt-get -y install libtbb-dev
sudo apt-get -y install libqt4-dev libgtk2.0-dev
sudo apt-get -y install libfaac-dev libmp3lame-dev libopencore-amrnb-dev libopencore-amrwb-dev libtheora-dev libvorbis-dev libxvidcore-dev
sudo apt-get -y install x264 v4l-utils ffmpeg
echo "Downloading OpenCV 2.4.5"
wget -O OpenCV-2.4.5.tar.gz http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.4.5/opencv-2.4.5.tar.gz/download
echo "Installing OpenCV 2.4.5"
tar -xvf OpenCV-2.4.5.tar.gz
cd opencv-2.4.5
mkdir build
cd build
cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D WITH_TBB=ON -D BUILD_NEW_PYTHON_SUPPORT=ON -D WITH_V4L=ON -D INSTALL_C_EXAMPLES=ON -D INSTALL_PYTHON_EXAMPLES=ON -D BUILD_EXAMPLES=ON -D WITH_QT=ON -D WITH_OPENGL=ON ..
make -j4
sudo make install
sudo sh -c 'echo "/usr/local/lib" > /etc/ld.so.conf.d/opencv.conf'
sudo ldconfig
echo "OpenCV 2.4.5 ready to be used"


With Ubuntu 17.10 Desktop version, how may I configure x11vnc so that I may log in remotely with a vnc client?

I do not have the same use case as you but it is similar and it might give some hints for the resolution of your problem if it is not yet solved. In fact I am remotely connecting from a smartphone using a console through SSH and a VNC client. My computer running x11vnc is currently under Ubuntu 18.04.2 LTS.

When the greeter is displayed, I run:

sudo x11vnc -safer -localhost -once -display :0 -auth /run/user/125/gdm/Xauthority (... other options)

Then I log in through a VNC client. Then as for you, I see a plain black screen. I then kill the running x11vnc.
Then I manually run (1000 is the number of the user logging in):

x11vnc -safer -localhost -once -display :1 -auth /run/user/1000/gdm/Xauthority (... other options)

I can then see my desktop (with my applications, ...) on my smartphone through my VNC client. I can then do remotely anything as if I were sitting in front of my computer using the keyboard and the mouse.

I think that the conclusion for you is that you need to run a second x11vnc with a different value for the -auth option. I think you can configure this as a "login" script which is executed directly after a given user logs in.

Note 1: as a side remark, please note that the -display option expects first :0 then :1, this made me lose a lot of time!

Note 2: for you 121 is the number for the user 'gdm', for me it is 125 but I found this through your question so thanks for that.

Note 3: I know that the question is more than 1 year old but since the question itself helped me I wanted to try to help in return as much as I can.


Scan entire disk in order, block by block, and also get file names

You can use debugfs to view and modify ext2/ext3/ext4 file systems on a very low level.

It has an interactive shell inside which you can run its commands manually (start it using sudo debugfs /dev/sdXY, where /dev/sdXY is the device your partition is saved on), but you can also let it run single commands only by specifying them with the -R parameter.

For example, to list the blocks that are allocated for the file /bin/ls on the partition /dev/sda2, try this:

$ sudo debugfs -R 'blocks /bin/ls' /dev/sda2
debugfs 1.43.4 (31-Jan-2017)
2922912 2922913 2922914 2922915 2922916 2922917 2922918 2922919 2922920 2922921 2922922 2922923 2922924 2922925 2922926 2922927 2922928 2922929 2922930 2922931 2922932 2922933 2922934 2922935 2922936 2922937 2922938 2922939 2922940 2922941 2922942 2922943

More information about this powerful tool can be found in its manpage by typing man debugfs. You can also type help inside its interactive shell to get a list of available commands.

Note: I am not sure about whether this tool performs well enough to be used to examine a whole partition at once. If you try that, you should probably not launch a new instance of debugfs per file to examine, but instead create a command script for it to run and use it with the the -f parameter.

The other way round to specify the block number and find which file it belongs to is also possible, but more complicated and it also can take a few seconds per step. Here's a transcript of an interactive debugfs session showing this:

$ sudo debugfs /dev/sda2
debugfs 1.43.4 (31-Jan-2017)
debugfs:  blocks /bin/ls
2922912 2922913 2922914 2922915 2922916 2922917 2922918 2922919 2922920 2922921 2922922 2922923 2922924 2922925 2922926 2922927 2922928 2922929 2922930 2922931 2922932 2922933 2922934 2922935 2922936 2922937 2922938 2922939 2922940 2922941 2922942 2922943
debugfs:  icheck 2922912
Block   Inode number
2922912 914862
debugfs:  ncheck 914862
Inode   Pathname
914862  /bin/ls


Which flavor I should use for a P4, 512 RAM?

You can try Xubuntu - is perfect for those who want the most out of their desktops, laptops and netbooks with a modern look and enough features for efficient, daily usage. It works well on older hardware.

Or, better, Lubuntu -  is targeted at PC and laptop users running on low-spec hardware that, in most cases, just don't have enough resources for all the bells and whistles of the "full-featured" mainstream distributions.


Problem solved:

Update 1
I reinstalled again, but got the same errors. I found this article helpful, and I was able to extract all the duplicity files into their incremental pieces. The article says to use rdiff to stitch together the files, but I'm not sure how easy that will be. Luckily my Lab Report that I really needed to restore was left intact. I'm going to try and fix the rest of the files next.

Update 2
I couldn't restore my backup using Deja-Dup, so I had to manually extract everything. I followed this guide to restoring by hand, and some of my files are back, but others that spanned multiple duplicity volumes were separated into incremental files. The wiki says "To recover data from incremental backups, use rdiff to stitch the files together." but I'm having difficulties.The rdiff manual has a section on restoring from incremental files, but I couldn't figure it out. I found another thread about manual restoration, and in it someone provided a script for joining multivolume snapshops. I ran the script, and all the multivolume snippets were joined. I got my files back.


Why is pcmanfm is still running after following the LXDE/XFCE Hybrid instructions?

Based on what I read here, it is necessary to comment out or delete the same line, @pcmanfm --desktop --profile lubuntu, from ~/.config/lxsession/Lubuntu/autostart. After doing this, no pcmanfm process runs and the xfdesktop is in charge.


How to list the size of a directoy and subdirectories and files inside it by terminal?

du -sh * | sort -h

will get you a human-readable ascending list of the sizes of files and subdirectories in your current directory,

du -sh

will summarize the current directory size.


systemd-timesyncd service is running in idle and doesn't synchronize time

I realize this is an old thread, but recently I had the exact same problem and I want to share my solution so others can avoid spending hours trying to figure it out.

The problem for me turned out to be the RootDistanceMaxSec parameter in timesyncd.conf. The default is 5 seconds; however, when looking at the NTP packets in Wireshark, the root dispersion value was around 10 seconds. I believe systemd-timesyncd was ignoring all the NTP packets because the root dispersion value was above the maximum.

To solve the problem, I modified timesyncd.conf by uncommenting the line that starts with RootDistanceMaxSec and updated the value to a number that was a few seconds greater than the root dispersion value I was seeing in the NTP packets. I then restarted my system and everything worked perfectly.

Hopefully this helps someone out there save a few hours.


Ubuntu 12.04 not booting after installation alongside Windows 7 in UEFI mode

I see you have chosen to install grub. But your laptop setup indicates it boot through efi.

So you need to install grub-efi not grub.

Re run the boot-repair program and choose recommended repair.

More information is available in How to boot Ubuntu from EFI/UEFI?.

Let us know how it went.


Why Déjà Dup is failing with gpg: decryption failed: Bad session key in Ubuntu 20.04.1?

Introduction comment - a possible cause of the issue
I had the same or similar issue. I followed some advice to create a totally new backup, but after some time the problem occurred again. I believe I could have - in a meantime - type in the wrong password, and after that I could not do backup anymore (just as Das Auge describled - thanks for the suggestion).
Quick answer - creating a fresh backup with newer Déjà Dup version
Installing the newer version (42.7) of Déjà Dup (from a snap package) and creating the fresh backup seems to solve the issue in my case as I had no need to restore anything I backed up before.

I removed an older version of Déjà Dup with sudo apt remove deja-dup.
I installed a newer version with sudo snap install deja-dup.
Because the newly installed Déjà Dup couldn't start for some reason, I had to remove ~/snap/deja-dup/common/.cache folder to fix that.
I started the application, set it up and created a fresh backup.

After the first backup succeeded I also tried creating new incremental backup (at least I believe that's what happens when You click a 'Back Up Now' button), typing in a wrong password (just to check the effect) and then a correct one and it worked.
Longer answer - possible options to restore the backed up data
I found a link to Wiki page considering this topic I believe (I found it in one of the comments in the issue on an official GitLab page of the project). Quotations of some parts of it below.

How to Confirm the Issue
First, if your backup files are on another server or on Google Drive, download the backup files to a local folder.
Then run the following command, replacing $BACKUPFOLDER with the path to the folder with your backup folders and $PASSPHRASE with your encryption passphrase:
for i in /$BACKUPFOLDER/*; do echo $i; if gpg --passphrase=$PASSPHRASE --batch --pinentry-mode=loopback --decrypt $i >/dev/null 2>/dev/null; then echo -e "^ \033[0;32mcorrect passphrase\033[0m"; else echo -e "^ \033[0;31mwrong passphrase\033[0m"; fi; done

If you see that some of the files have the correct passphrase and some have the wrong passphrase, you are affected by this bug.

Maybe in Your case, if You do have more than one backup file, just some of the files got encrypted using the wrong passphrase, but not the one You already tried decrypting. In my case, on the other hand, I haven't noticed any "correct passphrase" message.

How to Recover
If you are not actively trying to restore a file, (1) see below to
upgrade deja-dup to avoid the problem in the future and then either
(2) delete the files with the wrong passphrase and any backup files
after them to clean up your backups or (3) just start backing up to a
new folder.
Discover the Wrong Passphrase
It’s possible that you could discover what wrong password was used.

Open up your password manager (search for “Passwords and Keys” in your app launcher). Look for a password entry called “Backup
encryption password”. Open it up and click the “Show password”
checkbox. Does that passphrase match what you thought your passphrase
was? If not, that is probably the wrong passphrase that got used.
It might be a typo version of your regular passphrase. Try a few common typo versions using the command below, replacing $BACKUPFILE
with the path to one of the files that has a wrong passphrase, and
$PASSPHRASE with the typo version you are trying:

if gpg --passphrase=$PASSPHRASE --batch --pinentry-mode=loopback
--decrypt $BACKUPFILE >/dev/null 2>/dev/null; then echo -e "\033[0;32mpassphrase worked\033[0m"; else echo -e
"\033[0;31mpassphrase did not work\033[0m"; fi

If you can't figure out what the wrong passphrase was, that's still
OK. You can hopefully still recover the files you care about.
Manually Unpack the Files You Care About
Unfortunately, we have to perform some surgery on the chain of backup
volumes. The bottom section of the Worst Case page has instructions on
how to manually unpack volumes.
If you know the wrong passphrase, you can decrypt all the files needed
when manually unpacking.
If you don't know the wrong password, you are going to have to skip
some backup volumes. Because duplicity stores patches to files (rather
than full snapshots every backup), skipping volumes might create
problems when trying to patch files later. But if you're lucky, you
will be able to get all the data you need.

As I could not find the right passphrase I just decided to try installing a new version of Déjà Dup as I described it in the "Quick answer" section.


Can't install Apache 2.2.22 on Ubuntu 13.10

Apache 2.2 isn't available in the Saucy repositories. You should either work with it or downgrade to Precise Pangolin (Ubuntu 12.04).

If you force it, it makes yourself vulnerable to all sort of quirks and problems that can be in the future.

http://packages.ubuntu.com/precise/apache2

http://packages.ubuntu.com/saucy/apache2


Can I choose which OS I want to startup with while booting

Yes, if you installed Ubuntu after Windows 7, GRUB (GRand Unified Bootloader) will keep track of all the OSes on your system and allow you to choose which you want to boot on startup.

GRUB is what is known as a Bootloader, and Windows uses a transparent one that just boots the OS. GRUB, on the other hand, displays a text-based menu to allow you to choose what OS you want to load. It normally defaults to Ubuntu, and will load the default OS after a 10 second wait period, but you can manually choose and have it boot Windows.


Fresh install Ubuntu 16.04 : Not possible to boot Win10

Type on the terminal: sudo ntfsfix /dev/sda4.
And then remount again.


Ubuntu to W8 Boot failure : No DEFAULT or UI configuration directive found!

Live USB will not support create windows boot USB from Ubuntu. It allow to create only Linux boot USB from Windows.

Try winusb,

sudo add-apt-repository ppa:colingille/freshlight
sudo sh -c "sed -i 's/trusty/saucy/g' /etc/apt/sources.list.d/colingille-freshlight-trusty.list"
sudo apt-get update
sudo apt-get install winusb

With winusb you can do your need.


You need to make your server to declare the UTF-8 encoding:

Without UTF-8:

The configuration depends on your server. You can also change the UTF-8 (Unicode) to ASCII. The results are horrible, but at least are no gibberish.

iconv -f utf8 -t iso89 oldfile > newfile


How to remove unity-greeter with all additional packages?

you could do with

sudo apt-get remove unity*

that will remove all the packages that are belongs to unity. you said you have Xubuntu installed , so you no need to worry to execute that command because there is nothing harm to your system . it will remove only unity.


How do I connect bluez-alsa to an audio device?

I was under the impression that ALSA didn't support Bluez5 and I didn't gather from your other post that you're running Bluez4. So you may have some problems or other work to do. That being said I'll give you the general idea of using alsa and Bluez4.

Go through your usual pairing and get the device's address or use bluetoothctl/hcitool:

$ hcitool scan
Scanning ...
    XX:XX:XX:XX:XX:XX  NAMEOFHEADSET

$ bluez-simple-agent XX:XX:XX:XX:XX:XX

Next edit /etc/asound.conf (system-wide) or ~/asound.conf (userlevel)

pcm.btheadset {
type plug
 slave {
   pcm {
       type bluetooth
       device XX:XX:XX:XX:XX:XX
       profile "auto"
   }
 }
 hint {
   show on
   description "BT Headset"
 }
}
ctl.btheadset {
  type bluetooth
}

If this gives you any trouble you can try changing the first line to pcm.!default { which will force this to be the default audio device.

Reload alsa so that it picks up the changes in asound.conf and check that the device is added.

$ sudo alsa reload
$ sudo /etc/init.d/alsa-utils restart
$ aplay -L

Test out your sound!

As a closing thought here, did you decide to switch to alsa directly because you've had problems with specific wine applications? Normally the Pulseaudio-alsa is good enough for most games etc. that you'd run in wine and unfortunately the entire Linux audio stack is what keeps a lot of game developers away from Linux entirely so keep that in mind too.


With the shipped Ubuntu the HWE packs for the Kernel and X aren't installed. When doing a clean install of Ubuntu 16.04.02, the are automatically installed.

Installing the HWE packs, will install a newer version of the Linux kernel (4.8.0). This new kernel solved these glitches.

sudo apt-get install --install-recommends xserver-xorg-hwe-16.04

See https://askubuntu.com/questions/882896/old-kernel-with-ubuntu-16-04-2-update


How can I replace Xubuntu with Lubuntu on a Windows XP laptop?

Well I know you want advice that does not involve command lines but you only have to copy and paste one line into the terminal. (although you'll need a root terminal)

Open a terminal (Ctrl+Alt+T usually works)

type
sudo -i

enter your password

copy and paste (paste in a terminal is CTRL+SHIFT+V) in:

apt-get install lubuntu-desktop -y && apt-get remove xubuntu-desktop -y

That's it

the "apt-get install" bit installs the ldxe desktop environment and all the programs that go with it, the "apt-get remove" bit removes all of xubuntu. You could also run apt-get autoremove to make sure everything has gone. Or you can just reinstall by downloading lubuntu and selecting remove xubuntu and install lubuntu instead during the install process.


Why does "apt-get update" need sudo, but using "Software updater" doesn't?

Because you silently authenticate via PolicyKit when running the Software Updater. Part of the 'secret' is in the file

/var/lib/polkit-1/localauthority/10-vendor.d/com.ubuntu.desktop.pkla

more exactly via this entry:

[Update already installed software]
Identity=unix-group:admin;unix-group:sudo
Action=org.debian.apt.upgrade-packages
ResultActive=yes


Nautilus opens the home directory only, then proceeds to hang, and make the zsh terminal unresponsive to commands

This is pretty weird, but I opened my ubuntu the day after, and it is working fine, with no errors whatsoever. Honestly I have no idea why that fixed it, might have to do with the previous things that I did in the question, and that it needed a restart to take into effect.
Tldr; issue has been resolved following a restart.


Try:

sudo apt-get update
sudo dpkg --configure drbd8-source
sudo apt-get dist-upgrade


In a server, without a desktop environment, you are expected to manually configure networking. In Ununtu 18.04 and later, this is accomplished in netplan.

Step 1: Determine if you have a wireless device that has a working driver. Run the command:

lspci -nnk | grep 0280 -A3

Ideally, you will see something like:

03:00.0 Network controller [0280]: Intel Corporation Wireless 7260 [8086:08b2] (rev 83)
Subsystem: Intel Corporation Dual Band Wireless-AC 7260 [8086:c270]
Kernel driver in use: iwlwifi

If there is no entry for 'Kernel driver in use' then you will need to install a driver and, possibly, firmware. Use the pci.id, in my example 8086:08b2, and search Ask Ubuntu for details as to how to find and install the driver.

NOTE: This assumes that yours is an internal, that is, PCI wireless device. If yours is a USB wireless device, I will amend my answer to suit.

Step 2: If you have identified your wireless device and know that it has a working driver, find its interface name. Run the command:

iwconfig

You will see something like:

wlp3s0    IEEE 802.11  ESSID:off/any
      Mode:Managed  Access Point: Not-Associated   Tx-Power=off
      Retry short limit:7   RTS thr:off   Fragment thr:off
      Power Management:on

In this example, the interface name is wlp3s0. We will need that in the next steps.

Step 3: Amend the netplan file. Find out which you have with:

ls /etc/netplan

I suspect you will have either 01-netcfg.yaml or else 50-cloud-init.yaml. If yours is 50-cloud-init.yaml and your server is NOT intended to be a cloud instance, then you will need to disable cloud-init. Run the command:

sudo -i
echo "network: {config: disabled}"  >>  /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg
exit

This previous step is not needed if you have 01-netcfg.yaml.

Now edit your netplan file:

sudo nano /etc/netplan/XXX.yaml

...where XXX represents the actual name of the file you found above.

Amend the file to something like:

network:
  version: 2
  renderer: networkd
  wifis:
    wlp3s0:
      dhcp4: no
      dhcp6: no
      addresses: [192.168.0.21/24]
      gateway4: 192.168.0.1
      nameservers:
        addresses: [192.168.0.1, 8.8.8.8]
      access-points:
        "network_ssid_name":
          password: "**********"

Please note that the network SSID name and the password are enclosed in quotes. Netplan is specific about indentation, spacing, etc. Please proofread twice. Save and exit nano.

Of course, susbstitute your exact details here.

Example netplan files are found in /usr/share/doc/netplan/examples.

Follow with:

sudo netplan generate
sudo netplan apply

Reboot and check:

iwconfig

If you are connected, you will see the interface is associated with the name of the network:

wlp3s0    IEEE 802.11  ESSID:"mylilrouter"
      Mode:Managed  Frequency:5.745 GHz  Access Point: A4:2B:B0:DC:45:85
      Bit Rate=866.7 Mb/s   Tx-Power=22 dBm
      Retry short limit:7   RTS thr:off   Fragment thr:off
      Power Management:on
      Link Quality=60/70  Signal level=-50 dBm


Got the same problem with a Radeon HD4250. The problem is that there is no version.h file inside the /lib/modules/4.4.0-47-generic/build/include/linux directory. This is because in newer versions of the kernel the version.h file has been relocated. You can locate it with:

locate version.h

Since we already know which kernel version and what distro you are using all you have to do is link the missing file to the folder and start the installation again.

Source: Amd graphics card installation error on ubuntu 15.10


Video flickers when HDMI monitor attached

Figured it out!  At some point during my OS reinstall, I managed to re-enable Optimus in the BIOS.  I disabled Optimus in the BIOS again, rebooted, and voila!  All is right with the world again.


No sound on Asus Zenbook UX391UA with HDA Intel PCH

After some help from https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1784485 I finally fixed the problem.

It requires new kernel and some manual patching.

First download kernel source and extract it

wget https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.19.12.tar.xz
tar Jxf linux-4.19.12.tar.xz

Install necessary packages

sudo apt-get install build-essential libncurses-dev bison flex \
             libssl-dev libelf-dev

Copy kernel config

cd linux-4.19.12/
cp -v /boot/config-$(uname -r) .config
make defconfig

Add support for UX391UA

Add line to file sound/pci/hda/patch_realtek.c

SND_PCI_QUIRK(0x1043, 0x10a1, "ASUS UX391UA", ALC294_FIXUP_ASUS_SPK)

In patch format

--- patch_realtek.c.bck 2018-12-21 14:15:25.000000000 +0100
+++ patch_realtek.c 2018-12-30 16:13:23.970326312 +0100
@@ -6584,6 +6584,7 @@
    SND_PCI_QUIRK(0x1043, 0x13b0, "ASUS Z550SA", ALC256_FIXUP_ASUS_MIC),
    SND_PCI_QUIRK(0x1043, 0x1427, "Asus Zenbook UX31E", ALC269VB_FIXUP_ASUS_ZENBOOK),
    SND_PCI_QUIRK(0x1043, 0x14a1, "ASUS UX533FD", ALC294_FIXUP_ASUS_SPK),
+    SND_PCI_QUIRK(0x1043, 0x10a1, "ASUS UX391UA", ALC294_FIXUP_ASUS_SPK),
    SND_PCI_QUIRK(0x1043, 0x1517, "Asus Zenbook UX31A", ALC269VB_FIXUP_ASUS_ZENBOOK_UX31A),
    SND_PCI_QUIRK(0x1043, 0x16e3, "ASUS UX50", ALC269_FIXUP_STEREO_DMIC),
    SND_PCI_QUIRK(0x1043, 0x1a13, "Asus G73Jw", ALC269_FIXUP_ASUS_G73JW),

Build kernel

This command must be executed in top directory of linux source.

make -j `getconf _NPROCESSORS_ONLN` deb-pkg LOCALVERSION=-custom

Install new kernel and reboot

cd ..
sudo dpkg -i linux-headers-4.19.12-custom_4.19.12-custom-1_amd64.deb \
             linux-image-4.19.12-custom_4.19.12-custom-1_amd64.deb
reboot


Just disable keyboard stroke repeating via the UI

  Settings -> Universal Access -> Typing -> Repeat Keys

or from the command line like described in this SO answer


No sound in Ubuntu 13.10, tried everything

Your sound card manufacturer has failed so far to release a Linux driver. From what I have read on different linux forums there is some other driver for another sound card that could be compatible with yours. It looks like the ice1724 driver for the Envy24HT will work for your card in Ubuntu if you have VIA VT1723 chipset present on your sound card.

This is just a list of linux drivers for Ice1724, and you can check your kernel version, and also your Ubuntu architecture (32bit or 64 bit) and try to find some version of Ice1724 which is compatible with your system. Even if you find it, I am not sure it will work but this is the best I could do since there is no linux driver available for your sound card.

There is a similar problem with yours on this page, and maybe you can use some of the answers and suggestions in there to solve your own problem.


Burn your ISO file to the Media such as DVD or CD and Boot it to get install, you can't Open the ISO file using Firefox, Burn it using some software's such as Nero in Windows Machine, Use k3b in Linux to Burn the ISO file to CD or DVD


In the terminal you can see a list of all installed packages like this:

dpkg -l

Or, for example, write listing to a file:

dpkg -l > packages.txt


How to fix this keyboard bug in Minecraft?

move the us keyboard layout to the top of the layouts list (keyboard settings -> keyboard layouts)
so UBUNTU will know that the us layout is "standart".


Check the error.

1.You have initramfs error ?

which type of error shows ?, Blank screen or restating again and again.

In Starting time check the Grub config. Press e after check the image file location. If you can't find it. go next.

To get the boot CD / installation media and goes to rescue option. and repair your OS.
Grub rescue prompt, repair grub

Check the ABOVE LINK YOU CAN FIND MORE.


Unity notifications messed up after installing Gnome

It seems there is no priority or a single setting point to set which freedesktop notification daemon to run. I got such problem with XFCE installed on Ubuntu 14.04.

Unity notification launch xfce4-notifyd (XFCE styled notifications) as it was  the default.

Check for available notification services, example:

$ grep -r org.freedesktop.Notifications /usr/share/dbus-1/services/
/usr/share/dbus-1/services/org.xfce.xfce4-notifyd.Notifications.service:Name=org.freedesktop.Notifications
/usr/share/dbus-1/services/org.freedesktop.Notifications.service:Name=org.freedesktop.Notifications

Disable non needed ones, leave only the one you want, add a name extension suffix .disable:

sudo mv /usr/share/dbus-1/services/org.xfce.xfce4-notifyd.Notifications.service /usr/share/dbus-1/services/org.xfce.xfce4-notifyd.Notifications.service.disable

pkill xfce4-notifyd

Check

notify-send test

If there is no Gnome service file /usr/share/dbus-1/services/org.gnome.Notifications.service. Try adding notify-osd to start up applications. See How do I start applications automatically on login?. DBUS will try to launch the service only if there is no process already took that bus address ownership (org.freedesktop.Notifications).


Winecfg doesn't run anymore on ubuntu 14.04

You can remove your .wine configuration folder. Warning: if you installed any important programs in Wine's "C:" drive make a backup first. Open a terminal and run:

mv .wine .wine.bak

winecfg

Now Wine configuration should create a new wineprefix and open.


Yes, i got it.

It`s easy actually, code is:

nvidia-settings --assign 0/CurrentMetaMode="CRT-1: 1152x864_75 +0+0, DFP-1: 1280x720_50 @1280x864 +1152+0 {viewportin=1280x720, viewportout=1212x680+34+20}"

It took me some time to find right values, so this values are good for me - not for everyone.  You must play with those numbers to find the values that are right for you.


Synaptic package manager has stopped working in Ubuntu 12.04 Unity

I had a similar problem some time ago. I solved typing in a terminal:

gsettings set org.gnome.desktop.interface toolkit-accessibility false

But you sould provide further details to understand if you have the same problem I had.
If the above solution won't work, please edit your answer with verbose information, such as the output of running synaptic by terminal.


Forwarding Multiple port to Single port using nginx

It's also working...

server {
    listen 4442;
    listen 4441;
    listen 4443;
    listen 4444;

    location / {
        proxy_pass  http://10.1.1.2:5479/;
        include /etc/nginx/proxy_params;
    }
}


You might note that that particular version is smaller than all other releases by several megabytes so I suspect a faulty archive at the developer's end.

BytecoinWallet-1.0.11.amd64.deb is 539.9kb
BytecoinWallet-1.0.10.amd64.deb is 3.2MB

Here is a screenshot of the SourceForge download page to show this:

Good news is that the slightly older version seems to install fine:

wget --content-disposition \
https://sourceforge.net/projects/bytecoin-bcn/files/BytecoinWallet/BytecoinWallet-1.0.10.amd64.deb
sudo dpkg -i BytecoinWallet-1.0.10.amd64.deb

But I have not tested the application itself, only the install process:

andrew@athens:~$ bytecoinwallet --version
bytecoinwallet 1.0.10


Is there a suitable driver to connect a pentax optio s1 camera with ubuntu 16.4

Every device you connect to the system its mounted like a usb device. You see your camera storage in your file manager (Nautilus). Navigate throgh your device (your camera SDcard) then search DCIM folder. Your photos are likely be there.
Also I'm trying this software for commodity:
https://www.damonlynch.net/rapid/


How to customize the date format on the desktop (16.04)?

KDE Plasma 5 digital clock settings

From the Hour:Minute AM/PM to 24 hour clock with the ISO date.

Right click the clock widget, pick the 'Digital Clock Settings'

Appearance:

Use 24-hour Clock
Show date
Date format: ISO Date

More options to customize KDE plasma 5 clock: kde clock format: how to include the day in a non-tiny font?


I have tried to find the solution to the same problem, and for me it happens when firefox is open (sometimes), and closing Firefox solves the problem temporarily.

I wish I had more concrete info than this, but it might help someone else temporarily too, until a permanent fix is found.

More info: pulseaudio -k is another way to solve the problem temporarily, it will most likely stop videos played in browsers and the such so that refresh will be necessary. For some setups it might be a better solution than closing down the whole browser.

Working solution: (Edit: changed this to working solution as it has been over a week with no recurrence of this problem on 3 different machines)

Stumbled upon another answer.

In this case (As my system is of a higher version) we change

load-module module-udev-detect
to
load-module module-udev-detect tsched=0

in the file /etc/pulse/default.pa and then restart pulseaudio or our system. This has been working for about 3 days so far (From having the problem many times per days).

Documentation on tsched setting :

  Since 0.9.11. Use system-timer based model (aka glitch-free). Defaults to 1 (enabled). If your hardware does not return accurate timing information (e.g. Creative sound cards) you can try to set tsched=0 to enable the interupt based timing which was used in 0.9.10 and before.


VLC sometimes mutes sound and the image freezes

I solved this problem by going to Preferences  and re-initiaizing vlc completely.

There remains, however, a zapping problem (vlc stops playing after changing 4 or 5 stations) that I could not solve.


Did you try the script the YouTube poster suggested in his own comments?

Basically use xset to toggle the state of the led backlight.

#!/bin/bash
if [ -f /tmp/keyboard_light ]; then
  xset -led 3 && rm /tmp/keyboard_light
else
  xset led 3 && touch /tmp/keyboard_light
fi