Hello. I have had my iPhone 3G 16GB (white) since last July and just recently I decided to let my brother use it because I got the 3G S.
I chose Settings, General, Reset, Erase all Content and Settings in order to get all of my stuff of there. Now, when I try to turn the phone on, it shows the apple logo for a little bit, and then shuts off. Every time I try to turn it on it does the same thing.
Any ideas as to what's wrong? I tried plugging it into the computer and the phone turns on to the apple screen, then turns off after a little longer. The device never appears in iTunes.
The same thing happened to me, i fixed it by holding power and home button for 25 seconds while the iPhone 3G (mine is 8GB) was connected to the computer, then iTunes recognized it and I could finally restore it.