How to erase all data off of your Zune and start new. This can be a good option to try if you are experiencing problems with files on your Zune or it regularly becomes unresponsive.

1. Select Settings.

2. Select Device.

3. Select Sync Options.

4. Select Erase All Content.

5. Select Yes and confirm that you want to delete all content from the device.

All of your files will then be removed from the Zune.

This article was compiled based on information provided in the Microsoft article:
Error message on your Zune device: “The item is missing or can’t be played”