I have a system with Windows Vista and have been using Media Center to watch DRM-protected content for a while. Recently, I upgraded some hardware on my system, and now I can no longer view any DRM-protected content in Media Center. After some web searches, I found one of your old blog posts that describes a similar type of error message in Update Rollup 2 for Windows XP Media Center Edition 2005. However, that post and the knowledge base article it refers to appear to be specific to older versions of Windows.
I have read that some types of hardware upgrades can cause DRM to stop working in Windows, and I suspect that is what is happening to me. How can I reset DRM on my system so that I can view protected content inside of Windows Vista Media Center again?
The knowledge base article linked in that old blog post (located at http://support.microsoft.com/?kbid=891664) contains information that is applicable to Windows Vista as well as older versions of Windows, but it does not specifically state that it applies to Windows Vista.
According to this knowledge base article, you can reset DRM by deleting the files in the DRM folder on your system (but make sure to not delete the DRM folder itself because that can cause other problems on your system).
The default location of the DRM folder in Windows Vista is c:\ProgramData\Microsoft\Windows\DRM, but it might not be in the same location on every system. To reliably determine the location of the DRM folder on your system, you can look up the data in one of the following registry values:
For 32-bit versions of Windows Vista:
For 64-bit versions of Windows Vista:
Note - the DataPath value is in binary format, so you will have to double-click on the DataPath value in regedit.exe and look at the right-hand column of the Edit Binary Value dialog box that appears to see the plain text version of the path.