Yesterday, I ran ccleaner in the morning and it was fine. Then, went to run it later in the day and it gave an error message saying it couldn't find the files to run it. When I went into my system's Control panel and looked up the program, it showed it contained zero bytes and an install date of yesterday. Huh? So, I tried re-installing it and kept getting messages it couldn't as it couldn't find certain files. So, I purchased a paid version of the program and tried reinstalling that. Everything appeared to go well. I used the defrag program to run a defrag on my system to clean it up.