When you get that message 'Windows Explorer...' There is a link that tells you what to do to turn off the feature that is annoying you (data execution prevention).

Go to start...control panel...system...advanced tab...performance settings...data execution prevention tab...

Choose 'turn on DEP except for'...Windows Explorer

I'm not sure why this kept popping up on my computer...but since I have turned the feature off, I haven't had any negative effects. The feature says it is for protection against viruses, etc., but I have good antivirus software, so I am not too concerned!

Hopefully this will allow you to at least access the folder you are having difficulties with!

Good Luck