Stuck when shutting down
I’ve upgraded to High Sierra and it went fine. The only snag is that when I shut down, sometimes the pointer is left on a black screen and my Mac gets stuck. When I then force shutdown, I get a warning when next starting up that macOS didn’t shut down correctly. How can I fix this irritating problem?
This is a shutdown panic or freeze, and should never occur. It happens when macOS is trying to shut everything down but something brings it to a grinding halt. Your problem is identifying that something.
Test whether it affects another account on your Mac. If it doesn’t, then it’s likely to be old or broken software in your Home folder, probably in ~/Library, rather than an issue within macOS itself.
The best way to identify the cause is by browsing the log after such an “improper” shutdown, using Consolation ( eclecticlight.
co/downloads). Search for “system boot:”, which marks the beginning of the startup process, then work your way back to the entries before the shutdown to identify clues about what went wrong.
When you’ve located the last log message containing “system boot:”, take a look back at the previous shutdown to identify potential causes of your problem.