I have used CCleaner Professional for about 10Y on my Work Laptop, including the last year with Windows 10 Pro, after I obtained a new Laptop. However, once I upgraded to Version 1909 (Nov-2019 Windows 10 Release) in January, CCleaner has quit running. I can Uninstall and Reinstall new Versions successfully but no version from 5.65 onward will run on my Laptop with this version of Windows 10. I want to continue to support CCleaner but if it will not run on my Laptop, I will uninstall and look for competitors Software with the same functionality but runs on Version 1909 of Windows 10.
Can you give any more deail on what happens when you try to run it?
Where are you getting the CCleaner download from?
When did you purchase the licence for CCleaner Pro please?
Which security software are you using please?