In an earlier IBTimes UK report, it was announced that AT&T had decided to unlock iPhones of off-contract users. Furthermore, other earlier reports have discussed eligibility criteria and the service provider's method of unlocking the iPhone using back-up and restore from iTunes.
There is, however, a downside to this process - you are forced to compromise the untethered jailbreak during iTunes' restoration.
MuscleNerd, the brains behind the iPhone-Dev Team has unearthed a workaround to help you enjoy the untethered jailbreak while also successfully factory-unlocking the iPhone from AT&T, reports JBU.
How To Unlock iPhone 4/3GS Without Losing Jailbreak Using Redsn0w:
Step 1: Download Redsn0w 0.9.10b6 to your PC.
Step 2: Connect your iPhone 4 or iPhone 3GS to your computer using an USB cable and launch Redsn0w 0.9.10b6.
Step 3: Hit the "Jailbreak" icon which will initiate a normal connection.
Step 4: You will need to switch your iPhone to DFU mode. To do this you will:
- Press and hold both the "Home" and "Power" buttons simultaneously for 10 seconds, and
- Release the "Power" button while keeping the "Home" button pressed for 15 to 25 seconds more. The iPhone's screen will now turn blank.
Step 5: Wait for Redsn0w to detect your build.
Step 6: Once Redsn0w detects your iPhone's build, you will receive a number of options. Ensure that all options are unchecked with the exception of "Deactivate". This includes the "Install Cydia" option.
Step 7: Once Redsn0w completes the process your iPhone will be deactivated.
Step 8: Remove your SIM card and switch off your iPhone
Step 9: Switch your iPhone back on, connect to iTunes and insert your SIM. You should now receive an unlock message from iTunes.
That completes the procedure.