How To Enter Unlock Code Into Treo Mobile Phones Step By Step Instruction Guides
1) Remove Treo battery, unplug cable
2) Insert incorrect a not allowed SIM card (one the phone does not accept)
3) Power on your Treo, 'Sim not allowed' is displayed, click OK
4) Go to the dial pad, and use the stylus to enter code *#*#CODE#. Then press 'Dial'. (substitute the word "code" with the unlock code we gave you).
5) Phone will reset and display 'sim lock removed'