You might have to reinstall the OS. goto your subscriber's site and then look to redownload the OS. When you install it from your computer, it should ask you which programs you want to install. Also, make sure you resend your service books. On a Rogers phone, you just goto www rogers.com/bis. not sure about att though. Call them?
You need to have DM installed, next you need your OS installed on your phone and computer, then go into add applications, re-check bbm and install. You can find the OS versions in the stickys of the 83xx series thread.
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