I bought an iphone from someone and had it unlocked. I later had to take it into the apple store to fnd out why my phones main speaker (where you put your ear) wasnt working and I had to restore it back before they would even look at it. They ended up telling me I was shyt out of luck and now when I try to sync it to itunes it says my sim is not valid, and I am stuck on the emergency calls screen but I still see T Mobile at my top left. What should I do?
I had a similiar problem. There are mutiple fixes for the issue some work some don't if you are using a 2g phone the best thing to do is to remove itunes and reinstall, set it up in itunes as a new phone if it will let you if not jailbreak the phone using winpwn if it is a 3g use Quickpwn( this is if you are using a pc of course).