Instructions
Turn on your Xbox 360 and go to "My Xbox."
Select "Windows Media Center."
Write down the key that appears on the screen. The key is eight digits long.
Boot up your computer and open Windows Media Center.
Click "Tasks."
Click "Add Extender."
Type in your eight-digit key from Step 3 and continue the setup.
Go back to your Xbox 360 and go to "My Xbox" and then "Windows Media Center." The screen will now show Windows Media Center.
Play an HD movie on Windows Media Center.