sa lahat ng may error pag nag restore o update ng 4.2.1 try my solution

sa lahat ng may error pag nag restore o update ng 4.2.1 try my solution
Requirements
==========
1.redsn0w_win_0.9.6b5
2.4.2.1 _Custom_Restor.ipsw
3.4.2.1 official Restore.ipsw

Easy steps
==========
Must put your iPhone in DFU mode
open itunes 10.1 and press shift and select CUSTOM FIRMWARE 4.2.1
it will complete update without any error.and set will be emergency mod

Open Redsnow version 0.9.6b5
Select the 4.2.1 official Restore.ipsw
then, just do a jailbreak

just tick mark only
1. install cydia
3.install ipad baseband

when jailbreak done, then wait for a while ....
and when you see only apple logo dont do any thing
just open redsnow, then select the 4.2.1 firmware then press next
just only tick mark(just boot tethered right now )
And its all done.......