Details:-

I jailbreaked my iOS5.1 iPhone4 using "Redsnow Win 0.9.10b6" before two months and everything was working fine till yesterday.
But when I tried to reboot my device using the "Redsnow Win 0.9.10b6", the phone isn't starting up and just get stucked on half bitten apple logo. I done to it three times and showed the same. Then I used the itunes to restore the original iOS5.1, after extracting the software its showing the same.

Don't know what to do? get stucked everywhere! Can any one suggest a solution for this.

First try using Redsnow 0.9.11b4...they did have a few glitches with the old one...

if that does not work try using Absinthe 2.0.2


iClarified - iPhone - How to Jailbreak Your iPhone Using Absinthe 2.0 (Windows) [5.1.1]