I have used this for years, and have confidence in this as a good system for removing junk stuff from a PC to make it run better, and possibly eliminate some spying stuff (certain cookies). After years of enjoyment of this free software, they had a hack of some of their older versions. So, if you are running one of the versions below, please upgrade to 5.34.. it is free, I just did it for all my computers this morning.
The affected versions of the software are CCleaner 5.33.6162 and CCleaner Cloud 1.07.3191.
The company is urging users to upgrade to version 5.34 or higher (which it says is available for download here).
NOTE --- I also use MalwareBytes software for cleaning my computers of virus or potential useless, or harmful stuff. I have used this software for 8 years or more, and have confidence in it. One version of it is free.
https://www.youtube.com/watch?v=swlPf5X3sbk pretty good tutorial
They have had 2 billion downloads, it is a serious computer accessory.
How to install and run.