Refresh USB Ports
In device manager Uninstall EVERYTHING under the heading USB, reboot the PC let XP find and install new hardware.
Your equipment should now be recognised.
Repair XP by replacing corrupt files
in the run box, press enter and let system file checker find and replace missing / corrupt file in windows and explorer.This will take awhile to complete and you may be asked for the CD to be in the drive if windows is not preinstalled on the hard drive.
sfc /scannow problems