Turn the Zune over so the screen faces downward. This will ensure the battery does not fall out and pull on the cable.

The battery is not fastened to the inside of the case. It will fall out.

Pry up from the bottom of the Zune because the headphone jack will not allow you to remove the back case in one pull. You must slide the case up and away from the rest of the Zune.

The case is now separated. You can replace the case, if needed.