I have a SIM Card from my provider. The card works fine on both my unlocked blackberry pearl and my provider branded Alcatel OT-800. It will NOT read on my unlocked samsung vibrant though. Both of my unlocked devices are from T-Mobile. Anybody have any ideas? I got it to work.. after weeks of it not showing up. I plugged my phone in today and decided to see while it was plugged in. It showed up and I got all my contacts off of it. Weird.