A couple of weeks ago, my iMac (2017) started randomly shutting down. Once or twice, it did so while I was using it. I leave it on 24/7, but recently it has shut down during the night. I get the warning that it was shut down improperly and the question about supplying information to Apple about the event.
Any clues?
iMac Line (2012 and Later)
An abnormal shutdown can occur due to a power failure or some hardware fault.
The first possibility can be ruled out by using a good quality UPS. The second one can be more difficult to diagnose, but it would be instructive to determine if the same problems occur in "Safe Mode": Use safe mode to isolate issues with your Mac. Using a Mac in Safe Mode is generally inconvenient to use for any length of time, but if it shuts down while you were using it in that mode and after ruling out electrical power anomalies, have Apple evaluate it for a possible hardware fault: Contact Support.
Make sure you're using an intact electrical outlet and a good power cord. Desktop Mac power cords are generic.
An abnormal shutdown can occur due to a power failure or some hardware fault.
The first possibility can be ruled out by using a good quality UPS. The second one can be more difficult to diagnose, but it would be instructive to determine if the same problems occur in "Safe Mode": Use safe mode to isolate issues with your Mac. Using a Mac in Safe Mode is generally inconvenient to use for any length of time, but if it shuts down while you were using it in that mode and after ruling out electrical power anomalies, have Apple evaluate it for a possible hardware fault: Contact Support.
Make sure you're using an intact electrical outlet and a good power cord. Desktop Mac power cords are generic.
Hey John, the Safe Mode worked. It was godawful slow but it seems to have corrected my problem. Thank you for your time and courtesy.
Great! Thanks for the update.
Random Shutdowns
