Yeah after a fresh windows 10 install on my gaming PC due to my SSD failing, I installed CCleaner and unchecked the Avast ad at the bottom, Well, it ended up on my computer anyway....
I just Cloned Windows 10 to a SSD for my customers All-in-One PC, Decided the computer needed cleaned up, Installed a updated version of CCleaner, they had an old version, When it asked to install Avast, I unchecked the box, well its still installed Avast anyway....