I, recently, bought some drm protected videos. I had WMP 11 installed,but I had a computer problem so I had to roll back my operating system to it's original settings, which meant my player reverted back to WMP 10. I upgraded WMP but when I try to play a drm protected file, I get this error message "C00D11B1" which has nothing to do with drm licenses. Even the site I bought the clips from sent me a new password to acquire new licences but I'm not getting a popup to enter it. The error number has something to do with a sound card but my unprotected files play perfectly.Any suggestions? Thanks in advance.