Question about error message

I got this message recently when trying to play a file on Windows Media player. The file had played without problem until a few days ago.

Windows Media Player cannot play the file. The Player might not support the file type or might not support the codec that was used to compress the file.

i also got same problem few days back. finally i tried this it works good. so try this.
try to login as administrator in your system. then uninstall windows media player and download once again from microsoft website. it will work. sometime some softwares will only the administrator can uninstall or install the program. try this. this might help u.
-thanks