How to recover iPhone 3Gs Error 28 stuck in duf mode

I was trying to unlock my iPhone 3gs 4.2.1 and i had used redsnow and was done with jailbreak to 6.15 but just after that my phone stuck on the recovery mode so i went for downgrading it to 4.1 and i jailbreak it and now to boot i was using resn0w and after unlock with ultrasn0w(with4.1 and 6.15) The phone was able to reboot after the unlock but now it has stuck on dfu mode and now i am not able to reboot it with redsnow and i am not even able to restore(4.1 or 4.2.1) and later during restore the phone stuck white screen giving me an error 28.Is there any way to get it fixed?any help regarding this will be highly appreciated...

I think you can try this out in order to remove your phone from the DFU mode,just connect your phone to PC usb for power supply and just as you plug it in the usb port immediately hold and press the POWER+HOME KEY for 15 seconds seconds as soon as you do this properly your PC will detect your phone in a Normal way or recovery mode according to where you got stuck.

I don't know whether this might work for you but this method had surely worked fro me,what i did was simply removed my battery from the phone and then waited for a couple of hours and later i connected the battery again and then opened the iTunes and just restored the official 4.2.1 firmware.You can surely give it a try and i hope it will solve your problem as well.