1. Start the Windows Registry Editor, regedit.exe, by typing regedit in the Windows Run Command Line.
2. Go to HKEY_CURRENT_USER\Software\Microsoft\MediaPlayer\Player\RecentFileList.
3. Delete the RecentFileList subkey.
4. If you've also streamed content from the Internet, you can delete the RecentURLList subkey.
5. Exit the Registry Editor.
6. Restart the computer.
To keep certain files in the list, don't delete the entire key. Deleting individual entries within the key will get rid of the files that you no longer want in the Recent File List.