iPhone 3G S recovery 1600 error in DFU mode

[krystmasjones]

I have an iPhone 3G S with original firmware 4.26.08 running a PwnageTool 3.1.3 custom firmware. The phone has a SHSH for 3.1, 3.1.2, & 3.1.3 on Cydia. Computers are Snow Leopard with iTunes 9.2.1. & win7 Ultimate with iTunes 10. Every 3 months I do a custom restore using the same firmware file because of gradual slowness with amount of programs and files I have installed. Have done this twice with no problems. Did all Cydia and AppStore updates, transferred purchases to iTunes then did a full backup using AppBackup and AppCake. Did a reset on the phone and it wouldn't complete reboot, would loop between the pinapple boot icon and no charge (has been plugged into power until doing reset). I can put the phone into DFU mode but when attempting to do restore, get error 1600 on mac and PC. Phone doesn't go into recovery mode. Have tried using the default 3.1.3 firmware and get error that the phone isn't eligible for this firmware. Am able to get back out of the DFU mode but goes back to boot cycle.