XKitty

I've restarted it twice; once directly after installing some hardware updates (graphics and sound), and a second time after CCleaner wouldn't install. Still getting the same error.

I too am having this same issue. I tried to update CCleaner pro and had the above error pop up. Removed it in control panel and went to re-install from the site, and am blocked from re-installation. It appears the February windows update is not playing nicely with CCleaner (update KB4074588 - Windows 10, x64). The error that pops up when trying to re-install: "Error opening file for writing: c:\program files\ccleaner\ccleaner.exe Click abort to stop installation, retry to try again, or ignore to skip this file".