3gs 4.3.4 upgraded then downgraded to 4.3.3 now stuck on dfu mode
 

So I have 2 iphone 3gs that were upgraded to 4.3.4 (previously jailbroken and unlocked on 4.3.3)

I ran tinyumbrella server to downgrade to 4.3.3 using a custom firmware 4.3.3 since ipad baseband is installed on these phones. Restore goes good I restore to 4.3.3 with error 1015 and I run fixrecovery. everything goes smooth but the phone reboots on recovery mode then I ran redsn0w boot tethered (which should not be tethered) phone reboots and finally the phone is working. then I unplugged and the phones go into dfu mode. nothing shows on the screen and if connected to itunes it will prompt phone is in recovery mode blah blah.
any solutions?
I tried to restore to 4.1 but I get error 1600.

same here..........................

flash them with 4.1 version , without tinyumbrella , original not custom ,delete lines in host file and delete hosts.umbrella file in X:\Windows\System32\Drivers\Etc
you will get 1015 error , use ireb and phone will power on completly, just jailbreak ;)

IT'S work 100%!!THANKS from Yerevan!