I still get the warning when I start CCleaner manually or automatically. Interestingly, CCleaner is the ONLY application on my PC that shows this warning.
I'm running Windows 10 Pro 64-bit.
Running the latest version of CCleaner - currently, v5.39.6399(64-bit)
CCleaner's Options/Advanced: "Skip User Account Control warning" box is checked.
CCleaner's Options/Settings: "Run CCleaner when the computer starts" is unchecked.
CCleaner's Options/Monitoring: "Enable system monitoring" is checked.
I am an admin on the PC.
I've tried enabling "Run this program as an administrator" in the Properties/Compatibility settings for both the CCleaner64.exe and CCleaner.exe - no change.
Reducing the UAC Settings is a bogus solution. In this day and age everyone needs as much PC security as they can get!
ONLY AS A TEST - the only way I am able to start CCleaner without the warning is to set my PC's UAC settings to "Never notify" - (not recommended for normal operations).