"Did you accidentally upgrade your OS to 5.1 without saving your baseband? I've been guilty of that too."
Currently, the only way to unlock your iPhone with baseband 4.11.08 and 4.12.01 is through the factory unlocking service.
For AT&T subscribers, you can factory unlock it by contacting the AT&T Customer Support Service Center. However, you need to meet the set criteria before they can unlock your phone.
AT&T will unlock an iPhone under the following circumstances:
- The person requesting the unlock must be:
- a current AT&T customer or
- a former AT&T customer who can provide the phone number or account number for the account
- The iPhone was designed for use on AT&T's network;
- All contract obligations, including any term commitment, associated with the device to be unlocked have been fully satisfied; and
- The iPhone has not been reported lost or stolen.
In order to unlock your device, you have to contact AT&T at 800-331-0500 or by logging in to your account so you can contact them through email or chat. These unlocking methods usually take 5 to 7 business days.
For non-AT&T subscribers who want their mobile phones unlocked, you may opt to check some sites that offer factory unlocking services and pay some dollars to get it factory unlocked. However, we warn everyone to check on the credibility of the site as there are some who claim they are legitimate but are not.
iZone iHUB will run through few sites that offer factory unlocking services and will be giving feedback on legitimate and cheapest ones. For more updates on the latest, you may like us on Facebook or follow us on Twitter.