Originally Posted by cooldayr
Can't be done
Redsn0w will do it for 4S but only if you have your SHSH blobs saved from 5.0.1 and idr how for others gens but you still need SHSH blobs.
have you run Tiny Umbrella? If so, open it, click the advanced tab, uncheck set hosts to Cydia on exit, click X in top right to close it, then try restore in iTunes.
If you haven't used tiny umbrella, be sure that your hosts file doesn't have anything like this in it:
P.S. Hosts file is in C:\Windows\System32\drivers\etc
Originally Posted by Tekone
My phone has some hardware issue, will this remove the jailbreak completely ? My true question is will apple accept to repair my phone or not?
They may not do under warranty if jailbroken, doing a plain restore (just a simply left click restore) will revert the iOS to factory conditions, possibly fixing your error but if not removing Apple's ability to know that it was jailbroken.