I downloaded and installed the newest version (running Windows 10). When I started CCleaner at the end of the day, it would start to open to the main desktop and then almost close after no more than 2 seconds. This was when I was running in user (non-administrator) privileges. I tried it several times to prove that it wasn't an operator error.
When I right clicked and ran the program in administrator mode, the program seemed to work as usual. I used this to delete all the files.
But then I tried user mode again, it stayed up and I clicked "analyze". It should have shown very few files to be deleted. I had a Chrome browser open (writing this note) . But when I ran an analysis, it showed that there were files to be deleted - about what it showed before I ran the program in administrator mode. So I am not sure it did any cleaning at all.
Then without making any changes, I tried again to open up CCleaner and got the same shutdown. And when running again in Administrator mode, it did not show any of the files.