- 1). Insert the old SIM card into the phone you intend to use it with. (Most phones house the SIM card under the battery; refer to your user guide for details.)
- 2). Press the phone's "Power" button to turn it on. When the device starts up, "Enter PIN" or "Enter SIM PIN" will display if your SIM card is locked.
- 3). Enter in the four to eight digit SIM PIN. If you are unsure of the PIN, try using AT&T's default PIN of "1111."
- 4). Press "OK." If you entered the correct PIN, an "Unlocked" message will display. If you receive an incorrect code error, continue to the next step.
- 5). Enter in the default PIN --- or attempt to guess the PIN --- until a "PIN Blocked" message displays. (After three wrong SIM PIN entries, you will see this message.)
- 6). Contact AT&T customer support by calling 1-800-331-0500, and request the PUK (PIN Unblocking Key) for your device. (If you have a myWireless Account registered online, see the link in the Resources section for step by step instructions for obtaining your PUK through AT&T's website.)
- 7). Enter the eight digit PUK using your phone's keypad and press "OK."
- 8). Type in a new PIN code of your choice; pick a number you will remember. The PIN should be four to eight digits in length.
- 9). Re-enter your new PIN code to confirm. Press "OK." If all codes were entered correctly, your SIM card will now be unlocked and ready for use.
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