AT&T unlock instructions require you to restore the iPhone which will make you to lose jailbreak. If AT&T has already approved an IMEI unlock for your iPhone, follow the steps below to apply the official unlock without losing your untethered or tethered jailbreak in the process. The process is different for iPhone 4S since redsn0w doesn’t support A5 jailbreak yet.
Many users are asking me if they can unlock their iPhone 4S which is under a contract and will AT&T approve the unlock?The answer is ‘YES’. You can pay early termination fee. Besides, AT&T also sold no contract phones at full price that was locked. Those can now be unlocked.
How to Retain the Jailbreak after official AT&T Unlock
Deactivate iPhone 4 and iPhone 3GS using Redsn0w
Selecting deactivate, as the option in Redsn0w tool implies that it will deactivate your iPhone, meaning it would boot with the Connect to iTunes (iOS 4.x) or welcome screen (iOS 5) needing activation via original and/or official carrier SIM.
Step 1: Download latest version of Redsn0w 0.9.10b6 jailbreak tool
Step 2: Launch redsnow 0.9.10b6 and click the “jailbreak” button.
Step 3: Put your iPhone 4 or iPhone 3GS into DFU mode. Follow the on-screen instructions. To enter in DFU mode: Press the Home and Power together for exactly 10 seconds. Release the Power button and continue holding the Home button until RedSn0w detects the device.
Step 4: Redsn0w will now detect your build and will present you with number of options to select. Simply click on “Deactivate”. Be sure to un-check all other redsn0w options as shown in screenshot below. Tap “Next” to continue.
Step 5: Remove SIM card and turn off your iPhone.
Step 6: Connect iPhone to iTunes and insert the SIM card. Your iPhone 4/3GS will be unlocked with all jailbreak applications intact.
If the process doesn’t work for you, install SAM from Cydia repo and de-activated your iPhone via SAM. Follow the guide below.
Deactivate iPhone 4S using SAM
Those who use iPhone 4S might wonder how to apply an official IMEI unlock (carrier must issue the unlock first) on their devices without restoring and ruining their jailbreak, as redsn0w “deactivate” function cannot be applied since redsn0w does not work on iPhone 4S. To do so, use SAM (Subscriber Artificial Module) developed by @sbingner. This will allow you to do official activation on an iPhone without a stock SIM. Here are the steps you should follow, if you are already jailbroken on using Absinthe.
Step 1: Add repo in cydia http://repo.bingner.com and install SAM.
Step 2: Go to Settings > SAM and select “De-Activate iPhone”
Step 3: SAM will deactivate iPhone 4S and after you plug iPhone back to iTunes it will get activated and official unlock will take place. This will allow you to do official activation on an iPhone without a stock SIM
For those who are not jailbroken can simply press “reset all content and settings”. Needless to say that iPhone 4 and iPhone 3GS owners can also use SAM to deactivate and for also a redsn0w as well for the same reason.