Setting Windows Media Player as default in Windows 7
To set windows media player as the default media player in Windows 7, go to your "Start" menu, click on "Default Programs", click on "Set program access and computer defaults", click on "Custom", then click on the "down arrow to the right of "Custom". Scroll to the "Choose a default media player" section and select "Windows Media Player". Click "OK". Now the audio file should immediately launch media player and begin playing the audio file.