I have a 256 MB San Disk Cruzer Mini thumbdrive, and it works fine everywhere except for this Dell desktop I have. Specifically, the first time I plug it in, it works fine, but then if I try to plug it in again, the desktop does not acknowledge the existence of this USB device! And it does this for every USB thumdrive that I've borrowed from others to test if it is my USB's problem. Apparently, it's the desktop problem. Any insights on how to resolve this quickly? Any help will be appreciated!!!