A. When you play any media file on your computer, WMP uses a cache to track what video and music files you've accessed. Although this cache file is never transmitted and isn't in an easily readable format, another user accessing your system could review the file to determine what media you've been watching or listening to.

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WMP's cache file also can cause problems when you attempt to view a video clip before you've finished downloading the video from the Internet. When you begin to view the video, the cache file will store information about only the portion of the video you watched because the video is still downloading. The next time you attempt to view the video, the video will play only to the point where you interrupted the download process because that portion of the video is all the cache file believes the video file consists of.

To remove WMP's cache, perform the following steps:

  1. Open My Computer from the desktop.
  2. Navigate to \%allusersprofile%\application data\microsoft\media index (e.g., C:\documents and settings\all users\application data\microsoft\media index).
  3. Delete the wmplibrary_v_0_12.db file.
  4. 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.

Learn more: What keyboard shortcuts can I use in Windows Media Player (WMP)?