Q: Can't read my Windows (Boot Camp) partition from OS X I have a Boot Camp problem. Both OSes boot correctly, but when I'm in OS X, I can't access my Windows partition and vice versa. I know that I can't write, but it should be able to read. But I can't access the partition at all. 
In disk utility, I can see a disk0s4 grayed out where my Boot Camp disk should be. 
To add, I tried to go with a 3 partition setup (OS X, Windows 7 and a data disk). This is after a clean Lion installation.
Here are additional details on my setup in case it helps narrow things down:


*

*Installed a clean version of Lion after installing a new HDD.

*Using Boot Camp assistant to install/setup Windows partition.

*Before installing Windows 7 I created a new partition.

*Restart and install Windows 7 from CD/DVD.


diskutil list shows:
  GUID_partition_scheme                        *750.2 GB   disk0   
                    EFI                         209.7 MB   disk0s1
              Apple_HFS OS X                    270.0 GB   disk0s2
              Apple_HFS DROPZONE                208.9 GB   disk0s3
   Microsoft Basic Data                         270.8 GB   disk0s4**


A: NTFS support was removed in Lion, follow below to re-add it (you should be able to write to the drive as well, after installation)
install and enable ntfs-3g:
http://www.macupdate.com/app/mac/24481/ntfs-3g/
and install fuse_wait:
https://github.com/bfleischer/fuse_wait

A: It appears that OS X is not mounting the Windows NTFS partition. This is probably for one of two reasons:  either there is something wrong with the NTFS driver for OS X, or there is something wrong with the NTFS partition.  What happens when you select the NTFS partion and click "File->Mount" in Disk Utility?
If you have not installed any OS X software like NTFS-3G which modifies the built-in NTFS driver, the problem is probably with your Windows partition.  You can have a state where Windows will still boot from the partition, but the NTFS driver for OS X will detect that NTFS was not unmounted cleanly  and left the partition in an inconsistent state and refuse to mount it.  
In that case, you should reboot to Windows, and check the disk for errors (chkdsk /F).   Then see if you can mount it in OS X.

A: It is solved! You can find the solution here:
http://reviews.cnet.com/8301-13727_7-20090187-263/boot-camp-partitions-not-working-after-installing-os-x-lion/#postComments
Basically, I had same problem that I could not see my BOOTCAMP partition in MAC OSX. I had "Paragon NTFS read/write software" and this was the problem. When I searched for it in my mac spotlight (it is in top right corner of your mac environment) it was there. I opened it and chose "Turn the Paragon for mac OSX driver off" and then restarted my mac. Then the Bootcamp will appear again.
