Have you tried calling Tmobile customer service and ask for BB support?
Here's a link to our resident BB guru on the forums. Try private messaging him
and ask for help. Put a link in for this thread.
I have tried both the Technical Service and Online Help but none of them were really helpful as they told me that everything looks normal on their side and maybe in a couple of days I should call back. Yet when I called them I wasn't familiar with this MSL concept, yet you would expect them to have a clue on it. But thanks for the tip.
The MSL (Master Subsidy Lock) code is a code that locks the device to a certain network. It's like the SIM Subsidy Unlock code from T-Mobile and can only be obtained from the original carrier the device was purchased on. The good news is if your device was MSL locked, you wouldn't be able to use it for calls or messaging, so that should not be the issue.
Since the web browser is working and the applications are not working, it sounds like you may have an issue connecting to the BlackBerry network. The biggest things you'll want to do is to make sure you have a BlackBerry data feature (other features will not let you access the BlackBerry network) and make sure you have your device setup for T-Mobile services.
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