To complete the unlock, simply follow the instructions below: (WORKS BEST WITH AT&T ACTIVE SIM CARD IN PHONE). If you phone is activated, you can use ANY SIM card.
Make sure you update the phone to the latest iOS version as older ones may not work.
**SPRINT/VERIZON phones are not supported!****
1. Make sure you have the latest version of iTunes installed. Make sure there is an active SIM card inserted in phone.
2. Open iTunes on your MAC or PC and verify that you have Internet connectivity.
3. Connect your iPhone to iTunes by USB cable.
4. Back up your iPhone. How to back up: http://support.apple.com/kb/HT1766
5. Complete the setup assistant and restore your backup
6. After the process has finished, disconnect your iPhone, wait 10 seconds, reconnect to iTunes. ItвЂ™s fully unlocked now!
How can I tell my phone is unlocked for sure? Best way is by putting in a GSM (non-AT&T SIM) and seeing if you can dial out. Usually after restore process it will alert you that the phone is unlocked as well too. iTunes will not always show a message showing the phone is unlocked, so testing it with a foreign SIM is best bet.
If your phone is not unlocking or getting signal, PLEASE perform the backup/restore once again (above). Sometimes it takes upto 3 times to get it provisioned and unlocked. Also another solution is also trying to do another restore on another computer. Many times this has done the trick too.
Also if your phone is JAILBROKEN thismay not work due to the software being altered. Make sure your phone is NOT 06.15.00 (iPad) Baseband. If it is you will have to downgrade to the correct baseband. You can check YouTube or Google how to do this.
What if your phone shows up as NOT ACTIVATED?
You need to use an AT&T active SIM card to activate or get the last owner's billing ZIP code & last 4 of their SSN. Please make sure you DON'T confuse UNLOCKING with ACTIVATING. These are two different things.
If you're trying to use and old T-Mobile SIM you may need to get a new SIM first.
Older T-Mobile SIM cards are not compatible with iPhones.