well I had the same problem.
I actually found a fix... and instead of just disappearing, since it
was such a pain in the arse, I decided to try and help others.

Maybe it's just the holiday spirit... whatever lol.

anyway, I tried reinstalling windows media player and that didn't
work, I tried remounting my drive, no go, I tried deleting the DRM
folder and the registry keys, no go... eventually on a whim...
knowing the WMDRM files were messed I uninstalled and reinstalled XP
SP2... and it worked... it must have replaced the corrupt WMDRM files
in the sys32 folder.

what a pain in the arse.

GJ MS.

anyway the DRM issue even prohibited me from downloading MS updates...
go figure.

After I reinstalled SP2, I had to update the DRM through window media
player, but you could probably do it through windows update.

GL to everyone, I hope this works for you as well.