I have a usb thumbdrive that has stopped working in my PC yet works fine in
other PCs?
Is there some sort of automount that gets corrupted?
Check in Device Manager to see if it shows up
Then check in Disk Management to see if XP can see the "partition."
If the two above sees the drive, then your Explorer might be set to
not display the drive letter this drive is set to. Locate, download
and install TweakUI for XP (part of the Powertoys.) Then under the "My
Computer" section, in the Drives sub-section, make sure the USB flash
drive drive letter has a checkmark in the box.