Dell Dimension 9150 with Windows XP Media Center 2005 (Pro) … New at 06.03.06.

Five video files and seven music files had been preloaded, and have worked OK until a few days ago.

For no apparent reason, now when I try to play one of these videos, I receive the following error message.

Video Error

Files needed to display video are not installed or not working correctly.

Please restart Media Center and/or restart the computer.

and if I try to play one of these associated music files, I get this message

Windows Media Player has encountered an unknown error ( COOD 2798 )

I have since downloaded a pile of other videos and music files and they are all working OK. It is only the preloaded files that display as errors.

I investigated the Audio Error Code COOD2798 at the Microsoft help page

http://www.microsoft.com/windows/windowsmedia/player/webhelp/default.aspx?&id=C00D2798

It appears that the problem is due to the Windows Media Digital Rights Management (DRM) System.

My DRM folder is situated in C:\Documents and Settings\All Users. It is a protected operating system file and is normally hidden by default.

The above link advises resetting the Windows Media DRM System, but warns that this will delete the licenses for my protected files as follows :-

Warning :  Resetting the DRM system will delete the licenses for your protected files. To play, burn, or sync any protected files on your computer, you will need to download new licenses from your content providers. In some limited cases, it might not be possible to download new licenses for certain files. Before resetting your DRM system, contact your online store for more information about its policies regarding license download. In addition, if you are running Windows XP Media Center Edition and you reset your DRM system, you might not be able to play any copy-protected TV shows that you have previously recorded.

I've successfully adjusted my registry occasionally in the past, but the above warning has put me off, in case it causes more problems than it solves.

If I was sensible, I'd probably accept losing these video and music files, since all the others are OK.

But I liked these videos and music ..  and can't resist a challenge.  :smileyvery-happy:

I tried System Restore but this did not cure the problem. I also tried restoring my registry to an earlier date using ERUNT, again without success.

One possibility crossed my mind. I regularly make full system backups of my hard drive on to my external drive, using Acronis.

Is it possible that DRM sees this as me copying these faulty files, and automatically pulls the plug on them after a certain number of copies/backups ?

Would replacing the hidden DRM folder by its' equivalent older DRM folder in one of my older Acronis backups, be a possible solution ?

Or would this be a bit risky ? Also, Windows may block this change to a protected folder.

I also tried SFC without success.

Any suggestions ?

Scrumdown