I did a successful downgrade to 1.0.2 from a unlocked 1.1.1. I wanted to reinstall everything and get a fresh new restart because the 1.1.1 for me was really buggy. I upgraded back to 1.1.1. and tried using carnaval, but didn't work. So i tried jailbreakme.com, and that's when all hell broke loose! My phone doesn't boot to anything anymore. All it does is hang on the silver apple screen, then the small circle loading appreas and the phone just freezes. I have to do a hard reset to turn it off. I don't know what to do and Im really stressed out about this. I beg for you guys to help me!!! After this i'm just goin to stick with 1.0.2 and leave it be.
Just restore back to 1.1.1, and go to jailbreakme.com again.
To restore:
1. Turn off iPhone
2. Connect iPhone to computer
3. Turn on iPhone
4. When Apple logo shows up press and hold the home+power buttons together
5. Wait until iTunes logo comes up (about 20 secs)
6. Open iTunes, restore 1.1.1.
7. When done, do the jailbreakme.com again. Wait for the confirmation call (about 15 secs) and restart the phone.