I just bought a 3g off Craigslist that had "connection issues"
When I got the phone, it was Jailbroken, and Ultrasn0w was already installed. Yet I still got "No Service". (i'm using tmobile btw)
This is what I tried:
1. Restored firmware to 3.0,which is what it was running when I got it
2. Jailbroke with Redsn0w
3. Reinstalled Ultrasn0w via Cydia
Still I get a "No Service" message.
I've tried airplane mode off and on, 3g off, rebooting, etc.