Sound Device not found

Hello,
If i go onto windows media player a warning pops up saying:

"Windows Media Player cannot play the file because there is a problem with your sound device. There may not be a sound device installed on your computer, it may be in use by another program, or it may not be functioning properly."

when i go to properties, it says:

Legacy Audio Drivers
Device Type - Sound, video and game controllers
Manufacturer - (Standard system devices)
Location - Unknown.

It also says that it is working properly and does not need updated.


please help?