My iMac has suddenly slowed down to a crawl. Checking the Activity Monitor shows Windows 10 taking up over 50% of the processor time. Everything else is barely working. I don't see anything about an update. Nothing popped up telling me about an update. There was a note that flashed up about maintenance. I left the computer running for 3 hours, then shut it down and started it again after an hour. When Parallels started Windows the Activity Monitor showed the same high usage and the Mac slowed down again. I let it run another 3 hours with no improvement. What is Windows doing? Is this "maintenance" the cause of the high processor use? Is this a general thing with Windows 10 at the moment? I have to turn Windows off just to use the computer.
