Hey i have a similar problem. i have a iphone with t-mobile i accidentally restored it to the original factory settings i dont have any backup to the phone and i dont know which firmware to download. So far i tried restoring it through the recovery mode which is shift+ recovery button then i got a error (20) so then i got out of the recovery mode and into the dfu mode to try to retore it and i got error (1601) im not sure if this is happening because i'm using the wrong firmware or what....Any help would be greatly appreciated! thanks