New Samsung Galaxy S ii: everything seems to be working except for phone? Says mobile network not available? I got to thinking; when you switch sim cards to a new phone, do you have to contact TMoibile?
If you're switching operating systems (WinMo to Android, Blackberry to Android, etc), you need to contact T-Mobile to get that option turned onto your phone.
Calls should continue to work fine. It's just internet connectivity.
Check around this forum. I think that I read that you have to use the SIM card that came with the SGS II instead of your old SIM card. I could be mixing this up with AT&T, though.
Also make sure that Packet Data is turned on under Wifi settings.
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