I keep trying to play a song (mp3 format), but when I do Windows Media Player V.9 gives me this error message:

Windows Media Player cannot play this file because there is a problem with your sound device. It either is not functioning properly, is in use by another application or you dont have a sound device installed on your computer.

I have tried everything I know how to. Help?

Reinstall your sound card/device drivers and see if that fixes the problem...

ummm... How?

Install the drivers from the motherboard cd that came with the computer...

You need to get the model of your system. Go to the manufacturers website. Go to the support/downloads/drivers section find your model, then find the sound drivers listed for your model. Download them and run the download to install.

If you list you manufacturer and model, I may be able to give more specific instructions.