There may be more than one cause for this problem but I discovered what was happening in my situation and thought I'd pass it along in case it might help someone.
When I would tell Ccleaner to analyze, Windows would throw the low memory error message and either the computer would lockup, restart or maybe just Ccleaner would close. I tried adjusting the page file size and even adding more RAM but that didn't help.
So I started to watch the progress bar when Ccleaner was analyzing and noticed the crash came when it was trying to read the contents of the recycle bin. I also had Task Manager opened at the same time and noticed that when Ccleaner got to the recycle bin check the memory use skyrocketed up to almost !00% and then came the crash.
I checked the recycle bin and discovered it contained over 4000 items. I manually emptied the recycle bin and then reran Ccleaner without a hitch. Problem solved.
Apparently, when the recycle bin is too full this can happen.