You were probably updating/restoring your iPhone 3G which was unlocked and iTunes gave you error 1015. This is because your baseband is flashed to the iPad baseband (06.15.00) and iTunes could not update it so it gave you the 1015 error. You have two options at this point ; one is to update it to 4.2.1 using a custom firmware which matches your baseband or you can downgrade it to a lower 3.1.3 version. This guide will show you how to update it to the custom 4.2.1 firmware. Don’t worry, its easy to fix- just follow the step by step tutorials to get your iPhone running in no
Redsn0w 0.9.6rc16 (Windows)
iPhone 3G 4.2.1 Custom Firmware (Search Google) I’m working on this one right now because the other websites got shut down.
iPhone 3G 4.2.1 Regular Firmware
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