Do you mean that when you export audio/song in Music Maker it should play automatically in Windows Media Player?

If so, open Music Maker Program settings, click on Video tab and put check mark on "Automatically preview of exported material".

You can choose player of your choice such as Windows Media Player or any by following these steps IF needed.

First go to the exported songs put cursor on the icon of any of yours exported song then right click, from the menu click on Properties. Under General tab click on Change tab.(C) a window will be opened where you can choose some of your installed program as in this case Windows Media Player by clicking and press ok.

If you could not see Windows Media Player, in that case browse the program files and locate Windows Media Player's Icon and click on it then OK.

Later, exit all opened windows.

Hope your problem will be solved.