If you ever find yourself needing to restore your Galaxy S II to its factory default settings, there are two ways to to do so.
If you are running the international version of the Galaxy S II (GT-I9000) with a physical home key, follow these steps:
- Turn off your phone
- Press and hold the volume up, power/lock and home buttons all together for 10 seconds
- Go to Settings > Privacy > Factory data reset
Note : You can delete only data in the USB storage at the menu.