Invalid security token when updating Windows Media Center
Yesterday, one of my customers called me and told me that he received an error Invalid security token when updating Windows Media Center on Windows. I had never heard of this problem, so I did some research on this error message and discovered that it could be caused by a poor or corrupt Windows Media Center library. So I decided to rebuild the Windows Media Center library.
Invalid security token
The Library folder is a file protected by the system. We must first enable Show hidden files and folders and Show files protected by the system.