So my wife was using an unlocked iPhone 3GS for a while with no problems on iOS 4.x (I actually forget which sub version of iOS 4 it had on it). She was using the 06.15.00 baseband installed via a custom IPSW. Everything was good... Then she got an iPhone 4S and before we sold the 3GS we wanted to wipe her personal information, so I did a "erase all contents and settings". That resulted in the phone no longer being able to boot. So I tried to restore in iTunes using a custom 4.3.3 IPSW in order to preserve the baseband. At the end of the install I got a black screen. Now the phone seems to be perpetually stuck in DFU mode and cannot boot. If I try to restore again, iTunes gets stuck at "preparing iPhone for restore". RedSn0w gets stuck at "waiting for iPhone to reboot" and the only way I can get anything to appear on the screen is if I press "recovery fix" in TinyUmbrella which results in a white screen but nothing else works and TinyUmbrella then recognizes the device as "-Invalid". I've tried just about everything. Can anybody help me recover this iPhone or is it a lost cause?