Instructions
Turn on your Xbox console, and make sure it is connected to your home network before proceeding. The Xbox must be on the same network as your personal computer.
Click the "Start" button on your computer and open "Windows Media Player."
Press the "Stream" button on the options bar located at the top of the window. Select "More streaming options..." from the drop-down menu.
Locate your Xbox console in the dialog box, and allow media sharing by clicking on the parallel button and selecting "Allowed." Click "OK" to confirm the settings.
Navigate to the "Music Library" tile located under the "My Xbox" menu on the Xbox dashboard.
Select your computer from the list by clicking on the relevant name. If your computer is not automatically listed, select "Computer" followed by "Test Connection" to connect manually. Your music library is now available via your console.