Could you provide a little more info? When was the last time you installed windows updates? Have you changed anything in your system recently? Or did you just turn on the computer one morning to find WMC not working?
What about system specs? What other programs do you have open at the same time and do you use any other media centre software?
What about system specs? What other programs do you have open at the same time and do you use any other media centre software?
What kind of file was it? You said it required Windows Media PLAYER to play? Are you having problems with Media Player or Media Center?