I'm not a n00b at this by any stretch of the imagination. I've jailbroken a dozen iphones with no incident. When I got my iphone4 I couldnt find an untethered jailbreak so I used a tethered jailbreak with redsn0w using firmware iPhone3,1_4.3.1_8G4_Restore.ipsw which has worked just fine for months. Last night I deleted a program from cydia which rebooted my phone, and I went to my computer to boot tethered as I have done a dozen times since jailbreaking. I have two problems. 1. My phone won't enter DFU mode. (Or maybe it has and I just can't tell since I never get past the black screen) 2. Redsn0w is no longer recognizing that 4.3.1 firmware. Right now, my phone is chillin on the apple boot screen and flashing (or restarting) about every two minutes. Can someone please navigate me on how to fix this? And if there is an untethered jailbreak with a different firmware that came out that I wasn't aware of in the last few months, I'd love to know about it. Please help. I'm kinda lost without my phone.