Windows XP Home installs Maxtor 3100 (USB) properly if drive is connected directly to USB port on motherboard... but shows it as 'unknown device' if Maxtor 3100 is connected via the Adaptec USB2Connect (AUA 5000) 6-port USB-PCI board!
I dont know that there is a "fix" I have found external usb hard drives to be rather fussy about being connected thru hubs. the one I am using now will only work if I connect it directly to the mobo. That is just the way some devices are.