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User profile for user: wildpete
wildpete Author
User level: Level 1
9 points

Computer keeps shutting down

I have 27-inch iMac with Retina 5K display purchased Nov 2018. Currently running Mojave 10.14.6 and use mostly page layout and photo editing apps. Sometimes, with no warning, the screen goes black and the computer restarts. Applications tell me they were not shut down properly, and all the windows reopen themselves. This also happens when the computer is in sleep mode. When I wake it I have to log in as if it had been shut down. Again, same message from the applications that were open when computer had a problem. How do I find out what the problem is so I can try to fix it?

iMac 27" 5K, macOS 10.14

Posted on Dec 15, 2019 6:57 PM

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User profile for user: TheLittles
TheLittles
User level: Level 10
195,741 points

Posted on Dec 15, 2019 8:36 PM

wildpete Said:

”[..]I have no problems putting my computer into sleep mode. And some days it has no issues when I wake it. But, more often than not, I am now experiencing random shutdowns while working and also while it's in sleep mode.[...]”

———-


Try Reinstalling your Mac OS:

By reinstalling the Mac OS, nothing would be lost; it’s just that all corrupt files will be replaced; all files will be placed back to where they should be; removed system files would be reinstalled. Be sure you create a Time Machine backup prior to doing so. That may be the best way to go about this.


The Steps to Take:

  1. Back up your Mac with Time Machine - Apple Support
  2. Reinstall the Mac OS: 10.14 Mojave. You can reinstall it via:
  • Internet
  • Time Machine Backup
  • Flash Drive
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Question marked as Top-ranking reply
User profile for user: TheLittles
TheLittles
User level: Level 10
195,741 points

Dec 15, 2019 8:36 PM in response to wildpete

wildpete Said:

”[..]I have no problems putting my computer into sleep mode. And some days it has no issues when I wake it. But, more often than not, I am now experiencing random shutdowns while working and also while it's in sleep mode.[...]”

———-


Try Reinstalling your Mac OS:

By reinstalling the Mac OS, nothing would be lost; it’s just that all corrupt files will be replaced; all files will be placed back to where they should be; removed system files would be reinstalled. Be sure you create a Time Machine backup prior to doing so. That may be the best way to go about this.


The Steps to Take:

  1. Back up your Mac with Time Machine - Apple Support
  2. Reinstall the Mac OS: 10.14 Mojave. You can reinstall it via:
  • Internet
  • Time Machine Backup
  • Flash Drive
Reply

Computer keeps shutting down

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