staring to use it is not the right direction , if the owner gets it imea killed(if gsm) you might end up with a explantion problem if its gets tagged as stolen
I thought the 7290 was for cingular? so that would be your answer.
pink
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[rubbing his thumb and forefinger together]
Mr. Pink: Do you know what this is? Its the world's smallest violin playing just for the waitresses.
You get sim card rejected because the original owner has already cut this off. Sim card is now invalid. You may still see the phone number if you hit the space bar and go into phone mode. If you see blank phone number, that means the provider has de-provisioned the whole sim.
You can use the "mped" thing and find out if it is carrier locked. If it is, put a working TMO or Cingular sim card in and see which one works and you know the vendor. If the 7290 is carrier locked, black and without a provider name toward the bottom on the front, there is a good chance it is Cingular.
You know this whole issue is moot in my eyes. Anyone loosing a Blackberry has got to have reported it which in turn has got to have had its service stopped rendering the device useless. So in my eyes it is all an exercise in futility, the options are simple, 1) turn it to the police or if you want mail it to RIM they can decide what to do with it, or 2) just keep it for parts. Any other attempts after all that has been tried and suggested here already is useless and pointless.
If you call RIM and give them the PIN they could tell you the carrier you need to contact about it. The carrier should be able to track the IMSI off the SIM card. Problem solved?