My friend has an unlocked iPhone 3gs that we tried updating to the iOS software this morning. After downloading and installing the updated software, the phone is now on the wi-fi set up page that is the third step after the update downloads. The phone says no service in the top corner, and when connected to itunes it says no sim card is detected. please insert sim card then re connect.

I think this mess was caused because we tried updating it and it was unlocked. If anyone could please help with how to fix it?!?!