If your Mac restarted because of a problem
Find out what to do if your computer restarts or shuts down unexpectedly, or you get a message saying that your computer restarted or shut down because of a problem.
About unexpected restarts
Rarely, your Mac may experience a software or hardware issue that requires it to restart. When it starts up again, you may see a message saying that your computer was restarted because of a problem.
Unexpected restarts are usually caused by software installed on your Mac or by devices connected to your Mac. If the issue causes your Mac to restart every time it attempts to start up, your Mac may eventually shut down. Use the steps below to check the software and hardware on your Mac.
Check your software
If your Mac suspects that a particular app caused the restart, it may ask whether you would like to move the app to the Bin. Click Move to Bin, then contact the software developer to see if a software update is available.
Use safe mode to try to isolate the cause of the issue.
Check your hardware
Shut down your Mac, then disconnect all peripheral devices (such as hard drives or printers) from your Mac. If you have a desktop Mac, make sure only a display, keyboard and mouse or trackpad remain connected.
Then turn on your Mac and use it for the amount of time it would usually take for an unexpected restart to occur.
If disconnecting devices resolves the issue, isolate the issue to a specific device: connect one device at a time, testing again after each connection, until the issue returns.
If disconnecting devices doesn't resolve the issue, use Apple Diagnostics to test your Mac while your devices are disconnected.
If you continue to experience unexpected restarts, contact Apple Support.
Find out what to do if if your Mac doesn't start up all the way.
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