I have a 3G with the 3.0.1 firmware that I used Redsnow to Jailbreak. The jailbreak worked great and I have had no issues with the phone. I would like to upgrade to the 3.1.2 firmware and jailbreak but every time I try to upgrade the firmware with Itunes it fails and every time I try to restore it fails, I have even tried using Itunes to restore the new Jailbroken firmware and that failed. I can always use Redsnow to restore the 3.0 jailbroke firmware but I seem to be stuck. Is there a factory reset or newer version of Redsnow that I am unaware of? I only have access to windows pc's.