Hi, I'm brand new on here so please be nice. I just went through the jailbreak and unlock process on my 3GS, and am trying to put in my T-Mobile SIM card to use. I keep getting an error message popping up that says "SIM Failure" and then the upper left hand corner shows Invalid SIM. I have confirmed my baseband as 06.15.00. Any suggestions? ---------- Also, nothing is wrong with the SIM. It works in my phone from T-Mobile. I've also tried turning the phone off and on a couple times.