I am in Vista and CCleaner has been shutting down 100% of the time when I have secure deletion
enabled. However, If I keep of changing the secure deletion method, it works. I set the deletion method
to one overwrite, then back to 7. I run CCleaner, and then set it back to 1 overwrite. The next time I set it to 7, run it,
and back to 1 again. That is the cycle that has worked for me - but it's all about toggling through the settings.