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My sister has AT&T cell service, but recently messed up her phone.  (It's a Samsung it wet, and the "rice" trick didn't work.)  In a few months, her contract will be over and she will be able to get a new phone free, provided she enters another two-year contract.  (Which she may or may not do...hasn't decided yet.)
She has an older Nokia 3390B phone, and she would like to put the SIM card from her current Samsung phone into the older Nokia phone.  The SIM cards are the same size, but in order to switch them and be able to use the Nokia 3390B with her current provider, she would first have to unlock the Nokia.  Can you tell us how to do that?
Any advice, suggestion greatly appreciated.
Warm regards,

If both phones are AT&T phones, you can put the active SIM card into either phone. If the other phone is for another carrier, like T-Mobile or is branded by TracPhone or something else, then the AT&T SIM card won't work in the non-AT&T phone unless it's SIM unlocked. I hope this helps.

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I can answer questions on cellular phones, the physical device, the network, contracts, billing, ordering, porting and what to look for when purchasing cell phones. I am located in the United States. I am an expert on BlackBerrys, Treos, HTC devices and iPhones as well as cellphones and aircards. I have over 15 years of experience in both the wireless and wireline world with the carriers. I have a lot of knowledge regarding the wireless providers - their services, prices and policies, both GSM AT&T and T-Mobile) and CDMA (Verizon, Sprint/Nextel). I am very familiar with the individual devices and their specifications. I can also answer questions regarding BlackBerrys, iPhones and other PDAs, both Palm-based and Windows-based. I can troubleshoot most any problem someone is having with their cellular device or with the provider.


Over 20 years in the Telecom industry working for the carriers with individuals, small business, medium business and large corporations(Fortune 500). Also worked as a professor in Maryland for 10 years teaching telecommunications.

I belong to several organizations

Master's in Telecommunications

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Received several awards for papers that I have published over the years

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