If you don't remember the correct Arduino Yun/Yun Mini board address and you can't access to the board from browser then follow these simple steps:
- open the Arduino IDE;
- look your board address from Tool>Port>Network ports menu, as shown in the below image.
If you want more information on your board, follow this other guide:
- open Arduino IDE;
- select the correspondent COM and board;
- upload the YunSerialTerminal sketch from File>Examples>Bridge>YunSerialTerminal menu;
- completed the upload, open a serial monitor;
- Set correctly the monitor, choosing 115200 as baudrate and setting newline;
- click on Send button;
- digit the command: ifconfig ;
- they will appear three nets: eth1, lo, wlan0 , as shown in the below image;
- look eth1,if the board is connected via Ethernet cable, then inet addr is your board address.
- look wlan0, if the board is connected via Wifi network, then inet addr is your board address.
Now you can use this board address to access to your board from browser.