I recently ran a registry clean using CCleaner, and since I have done this I am no longer able to run .exe files.
Fortunately before I made this change I saved a registry backup to the My Documents folder.
Unfortunately when I look in the Tools section of CCleaner, I do not see this important backup .reg file listed, though it does exist in My Documents.
I must restore my registry using this file, but I am unsure as to how.
Any help would be greatly appreciated.

-Doc

Right-click on the REG file >> Merge.

If you still have trouble with .exe file associations just use the fixes here

XP
http://www.dougknox.com/xp/file_assoc.htm

Vista
http://www.winhelponline.com/articles/105/...dows-Vista.html

I would use this method first, if you knew the problem was caused by CCleaner as it would be 100% safe to merge it.

If this failed, then I would try Hazelnut's suggestion secondly.
I have used the association fix in time past, & it sort of worked, while causing other things to act a little strangely if you know what I mean!

I'd say scan your computer for malware too, as they can be the main cause.

The below is a .REG import for fixing the ability to open EXE files, the fix is from years ago that I got from some anti-virus website, never had to use it myself though.