Windows Media Player keeps a history of the media files you play in it. Sometimes this information can be picked up by spyware programs (or Microsoft), or can be seen by other people who use your PC. It's a good idea to clear out and unwanted tracks from Media Player.

Open My Computer from the desktop.
Navigate to all users\profile\application data\microsoft\media index
(e.g., C:\documents and settings\all users\application data\microsoft\media index). Delete the wmplibrary_v_0_12.db file.
Close My Computer.

The next time WMP starts, it will recreate the cache file. You can write a script to delete this file each time Windows starts, or you can set the cache file attribute to Read Only by opening My Computer, navigating to the cache file, right-clicking the filename, selecting Properties from the context menu, and selecting the Read Only check box.

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