If your baseband is 06.15 then this is for you :P
download ireb
MEGAUPLOAD - The leading online storage and file delivery service
download 3g 4.1 custom firmware
MEGAUPLOAD - The leading online storage and file delivery service
run ireb then
Open up itunes click shift and give custom firmware and it will restore with out any problem.
If Incase stuck on sn0wbress logo or apple logo.
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use redsn0w using original 4.1 firmware and select unthethered
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Once it unthethered open redsn0w and install cydia only then i will not stuck on logo
100% solution
Dont forget to press thanks