Hello and welcome to Android Forums!! What was you doing at the time the phone shutoff on you,and is your phone rooted? There is a bunch of factors that play in this,so if you can add some more info about the situation,we might be able to help you further.if you like,you are more than welcome to join Android Forums for free,yes free no strings attached!! And there is Forums on the galaxy s2 that could help you out further too,just click on the link below after what a life and create a account and search threw the phone forums until you find yours.Thank You and hope to see you in the forums!!