I'm positive this has been asked before. My husband just bought me an unlocked Cingular 8700c BB. I have T-Mobile service. I put in my SIM Card and it's saying Invalid SIM. When I go to Settings>Network It'll come up
T-Mobile but then go back to Cingular. I've gone to Settings>Options>Advanced Options>SIM Card and typed in MEPD . SIM is disabled; Network is Active; Network Subset is Disabled; Service provider is Disabled and Corporate is Disabled. I was told if Network still says its Active, that means it's still locked. Is this true? I'm just trying to figure out what I need to do to make it work with my SIM Card. If it's still locked, is there a website I can go to to get it unlocked? I'd hate to think my husband wasted money on getting me a gift I really wanted. Thanks!!!

Yes, it is locked to the Cingular Network. Try GSM PhoneSource - When Only The Best Will Do, Adam runs a great service.

Thanks. Will check out the site and see if I can get it to work with the code. Thanks again and Happy Holidays!!!

No problem, happy holidays to you too!