USB device missing

[bogart]

I am having a problem with a pc not seeing a Creative Zen Nano Plus. PC number 2 sees it fine. Only difference I can see between machines is some of the usb settings. The one that doesn't recognise it has the following usb listings in device manager.

USB Composite Device x 1
USB Root HUB x5
USB Universal Host controller x 4
Enhanced Host contoller X 1

What does confuse me somewhat is that the machine has 6 usb ports now I would have thought I needed 6 controllers not 5 as above. Additionally looking at the items individually under the device usage most say device enabled, except the composite controller, root hub 1 and usb host 3 (PCI BUS 0, Device 16, function2) all of which are greyed out. I have checked my second pc and all are device enabled. I have loaded fresh drivers from microsoft and VIA but still to no avail. Unsure where to go from here. All other USB devices are seen correctly including a Zen Sleek Photo. Both machines running XP pro, with SP2

Any advice gratefully received.

[killie99]

what drive letters are already used on your pc's? I had a problem where a flash drive wouldn't show because it **HAD** to have a drive letter C, D, E, or F and I had all these drive letters already used. Moved one of the dvd drives to drive G and the flash drive then worked, might be worth looking into.

[bogart]

Hi, its not a drive letter problem because if I connect a card reader it shows J,K,L and M ( other units up to H) so assigning it a drive letter isnt the case, damned annoying though! As i said other PC sees it straight away no messing, machines are identical except for this greying out of certain portions in device manager on problem machine.