I got a problem with my sound device, I try to play music on windows media player and it says that my sound device may not be installed, it might be used by another program or it might not be functioning properly.
I might not have a sound device hardware...

Close every program running including ones running in the background, and try to play music with windows media player, if it doesn't work, try to play music with another program (itunes, jet audio, blah, blah, blah)... if none of this works uninstall the drivers for your speakers then install them again
If u still have no result, beats me lol
But I hope one of these works

I got a problem with my sound device, i try to play music on windows media player and it says that my sound device may not be installed, it might be used by another program or it might not be functioning properly.
I might not have a sound device hardware......
There is no sound driver installed in your PC. Install the drivers for the sound card and restart your PC then try to play the music in your windows media player...

Also might want to make sure that your audio is enabled in the bios