[Microsoft said "Don't use CCleaner Registry!"]

Hmm, well this thread isn't a particularly good advert for using CC; as a matter of interest why does it have such an adverse efect on the registry. BTW I've used the registry tool on many occasions with out problem, maybe I need to be more cautious.

[File deletion.]

Options>settings>file deletion; what is the difference between normal file deletion and secure file deletion? Under secure, what is the difference between the 4 options provided?