Hello all, I've been trying to downgrade to iOS 4 from iOS5b4, but for some reason, nothing I try works. Everything seems to get me error code "1604" and then my phone stays stuck in recovery mode. I've tried using iTunes 10.4, 10.5b5, 10.5b2. I've also tried to downgrade to iOS 4.3.3, 4.3.4, 4.3.4. I've tried using TinyUmbrella, but that didn't work either. I put my phone in DFU mode, and iTunes just stays stuck in the "Preparing iPhone for restore" screen. If anyone has any suggestions, I'd love to hear them. Thank you.