Today, the long-waited macOS high Sierra was finally arrived. I can’t help trying it after downloading it for several hours. But out of my expectation, the updating is stuck during the process of rebooting system. The a big file folder appeared at the center of the dark screen(see attached pictures). It popped out every 2 seconds. Very annoying!
I tried to turn off my MacBook Pro (Retina, 13-inch, Early 2015) and the problem persisted. How should I do it?