I had the same problem.

Control Panel...System...Advanced...Settings...Data Execution Prevention

Add Windows Explorer to the list and check it.

You can read about DEP while you're in that window. It's supposed to protect your computer from viruses wreaking havoc. It just annoyed me, though, and I don't think I've had any problems since I made this change (it's been quite some time).

Hope this helps

Dano