Recently CCleaner won't start in my macbook Pro. on my imac it's work great! (same OS)
My mac is a MCPro retita mid 2012.
The OS is 10.13.1 bat i try with older OS version.
I also tried previous versions of the program, but nothing in fact.
I noticed that the serial number of the mac was missing in system preferences.
I used "blank board serializer" to fix the same.
now CCleaner works!
I hope I was helpful. regards