I've had this problem before on a couple of my windows machines, I searched around and couldn't find any cause agreed upon, but it usually seemed to come up for me after using disk image software (as in Daemon Tools, etc.). If I didn't have a floppy drive to begin with, uninstalling the corresponding drive usually solved it. If I did have a floppy (or otherwise existing drive for the letter it was asking), then usually mounting something, anything, on the drive usually solved it.
But yea, this isn't a toribash bug, I think it's just a common problem with XP.