Is CCleaner safe to use on solid state drives? I know you can overwrite an SSD so many times before it fails. I was running CC nightly before retiring for the evening, so I am sure CC is safe, but how often should I use it? Along with ZA protection it is a pretty formidable internet security tool.
CCleaner's cleaning functions are fine to use with SSD's.
With the caveat that you shouldn't need to use 'Secure file deletion'. Only use 'Normal file deletion'.
Secure deletion is not needed on a SSD, and just gives unnecessary overwrites.
Also avoid 'Drive Wiper' and 'Wipe Free Space' (which is temporarily disabled anyway while a potential issue is investigated), again they are not needed with a SSD and would just give unnecessary overwrites.
Not SSD related, but if you have Windows 10 then I wouldn't use the registry cleaner either. It can cause problems with Win 10.