Windows 7: Autohide doesn't deactivate

I'm running windows 7 home premium 64bit and my taskbar is set to autohide, but whenever I move my mouse to the edge of the screen, it steals focus from whatever program I am using when it reactivates! This means that if I'm playing a game and I move my mouse to the right edge of the screen the reactivating taskbar forces me to the desktop. When I tried to turn off autohide, it didn't work and when I ran settings again the checkbox was refilled. Is there any way to force a reset to factory defaults through a registry edit or is there a file I can download to force explorer back to factory defaults?

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I don't know if this will help but try this SFC /SCANNOW Command - System File Checker
Jerry