Sony Ericsson K790 / K800

Hey I just got the phone today, replaced my rokr and have already run into trouble. When I connect the usb to transfer some test pics i took it says it cannot recognize it. I installed the software and tried...same thing...unistalled reinstalled...same thing..I pput it in once and it said it detected k790 blah blah then it said it did not install properly and I went to the program and it said phone is not connected....Any suggestions?

Thanks