Restore A Bricked 3GS New Or Old Bootrom And Can Also Update Your Working 4.1 iPhone 3Gs To 4.2.1 On 6.15.00 Baseband
IF Your iPhone Is Not On 6.15.00 Baseband OR Has Not Crashed While Installing It Then these steps are NOT For You!
Things you need to proceed:-
1>iPhone 3GS 4.2.1 Custom Firmware.
2>iPhone 3GS 4.2.1 Original Firmware.
3>Redsn0w 0.9.6.b6.
Steps you need follow:-
1. If Updating Or Restoring To 4.2.1 Open Redsn0w And Select The Official Firmware, Then Deselect ALL Options And Only Check "Just Enter Pwned DFU Mode Right Now"
2. Once Finished, Open iTunes And Hold Shift Or Option On Mac And Left Click Restore In iTunes, Then Select The 4.2.1 Custom Restore File For 3Gs ( Depending On Your Device)
3. After Restore iPhone 3Gs Is Locked You Must Jailbreak So Watch...