I wanted to update my iPhone 3GS from 3.1.3 to 4.2.1 so then I followed METHOD: First use Redsn0w 0.9.6b6 to put your iPhone in Pwned DFU mode so that it is able to accept Custom Firmware file. When iDevice in Pwned DFU mode then simply open iTunes and hit Shift + Restore (Windows) or Option key + Restore (MAC) and load in Custom 4.2.1. Onces all the proccess was done iPhone did not reboot but went straight into recovery mode. so to take it out off recovery mode I used Tinyumberalla which gave me an option "Fix Recovery" When I click on Fix Recovery it did its thing on the phone and gave me a message Unable to find gBdevlist unable to find fs_mount Unable to find fs_unmount Unable to find fs_load_file Greenpoision Initialized and then does some more things again and stops at Unable to mount user filesystem! AppleBCMWLAN: :handleIOKitBusyWatchdogTim eout():Error,no successful firmware do wnload after 60000 ms!! Giving up.... I dont no what to do Please Help.