Code 41 is explained here with a suggested troubleshooting procedure:
http://support.microsoft.com/default.aspx?scid=kb;en-us;310123#XSLTH4592121122120121120120
This is a driver issue, and I'd bet it's related to the upgrade from ME.
There's a registry hack here:
http://www.hardwareanalysis.com/content/topic/35761/



Russ Cox wrote:
> I have a Compaq 7478 computer running Windows XP home (SP2) upgraded from ME. It has an AMD K6 cpu at 530 MHZ, 312 M RAM. Seems to run applications ok, but won't recognize the DVD ROM and CDRW.  Device Manager shows one of the drives, probably the DVD ROM, but shows the device name as gibberish.  When I remove the driver, it reinstalls a driver from XP, but gives an error message " Windows has successfully loaded the device driver but can't find the hardware (Code 41).
> I have replaced the IDE cable, swapped in another CDROM, but neither device will read a CD.
> I cannot get it to go into setup with "delete" or safe mode with F8 and it won't boot from a CD or a floppy.
> I also tried an external CD RW. It registers the USB device, but won't show the external drive on "My Computer".
> Any suggestions for restoring this machine to operation? It was given to me to refurbish as a suppoosedly working machine.
>
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