Tracks missing from Windows Media Player? Try clicking Start > All Programs > Accessories. If you're using XP you should select the Command Prompt, or in Vista or Windows 7 right-click it and choose Run as Administrator.

Switch to the folder containing your music using the cd command (for example, cd music cd my documents\my music), then type "attrib -s *.* /d /s" and press [Enter].

Once complete, open Media Player and press [F3], or choose Tools > Advanced > Restore Media Library (in Windows 7) to access all your music again.