How to reload OS on SMT5600?

[Guest tinatorres]

My phone won't boot up. I finally got the hard reset timing to work - thanks to the great vid instructions - but after hitting the 0, I don't get to the rest of dialogue screens (I have done the hard resent sucessfully with another smt5600 just recently and am faily confident that it's not a user error ;> ). It just hangs and hangs at the blue windows Mobile screen. My hunch is that some OS file got corrupted somewhere - I don't think it's a hardware issue. Does anyone know how I can get the OS reloaded on the SMT, starting from where to get the OS to how to do it? I got the phone on e-bay. It's unlocked - a previous AT&T phone.... I am a tmobile customer... any thoughts and pointers would be appreciated!