Have you tried updating the drivers?
Just a guess. This happened to me once with the cdrom, it just disappeared.
Another thing to check for would be viruses. Make sure the virus definitions
are up to date and do a full scan.
These are just a couple of things off the top of my head, it's late here so
I can't think straight.
Hope it helps though.
Michele Sayer.

                         PCBUILD's List Owners:
                      Bob Wright<[log in to unmask]>
                       Drew Dunn<[log in to unmask]>