Microsoft Knowledge Base Article 810422 contains the following Symptoms:

If you try to use Windows Media Player to play media files that are licensed using Digital Rights Management (DRM) technology, your existing licenses may not work correctly, or you may not be able to acquire new licenses. You may receive one of the following error messages:

The licenses for your media files are corrupted. (Error code 0xC00D2754)

Windows Media Player cannot play the file because the associated license is either corrupted or not valid. (Error code 0xC00D11D6)