I,m using the pro version under Windows 64 Pro Build 17134.137 Version 1803. There is something wrong with ccleaner v544, as version 5.43 is doing well. By the way the /reastart command line was doing well. As you suggested, I installed it complete new, now it is running well. So the update didn't work exact.
I got the same problem and also the /shutdown command doens't work eather. I changed back to version 5.43 and have no problems-