I used CCleaner for the first time the other day. I actually read the beginners guide which states in effect that it is suggested to leave everything in the default mode. Well I did that and now I have to reconstruct my Quicken checkbook (yea, yea...I know I should have had a a backup!!) And yes I do know that it was CCleaner as I have not run anything else nor have I downloaded anything else during that time frame. I like the idea of CCleaner but at this point there is no way that I could recommend it to anyone nor will I use it again. I'll just keep cleaning the old fashioned way!