OK... 1st, of all the PC recognizes the DVD/CR-ROM? You yourself said that it can see/open/use regular CD's. So it's not the physical drive iteself. 2nd, were you trying to watch DVD movies with this drive? If so what DVD decoder software or hardware were you using? 3rd, by default WindowsXP will not play DVD's (either music or video) without a DVD (hardware or software) decoder. You need either or to properly use the DVD drive for this purpose. If you were using software decoders, were you using full retail DVD software or trial DVD software (there is a difference)? If they were full retail versions are they the latest versions? WindowsXP has issues with older DVD decoding software and needs the latest versions. 4th, did you verify that your DVD drive is XP compatible from the Hardware Compatible List? h**p:www.microsoft.comhcl I hope this may help you on figuring out what the problem is.