macOS upgrades can take between 40 minutes to 3-4 hours to complete. If the installation seems stuck for a few minutes, let it run for a while and see if it completes or makes any progress. If the install fails to finish after several hours, try the steps below to troubleshoot or restore your computer from a Time Machine backup.
Troubleshooting Steps
- Hold the power button until the computer shuts down.
- Boot into Safe Mode
- Follow Apple's steps for the CPU that your computer has to boot into Safe Mode.
- If you reach a login screen, log in and let it load for a minute.
- Restart the computer normally and see if it boots into the new operating system. If not, continue below.
- Boot into Recovery Mode and run First Aid on your hard drive
- Turn off the computer.
- Turn the computer on and hold the Command and R keys until a loading bar appears. If you have an M1 Mac, hold down the power button until you see "Loading startup options" and click "Options"
- Select Disk Utility.
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- Select Macintosh HD on the left and click First Aid.
- Reinstall macOS
- Close Disk Utility.
- Select Reinstall macOS and follow the steps. This will not delete any data on your computer.
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If you are able to log in normally and see that your computer is running a new operating system, you should be all set.
If the install is still failing, you can restore from a Time Machine backup with the instructions below, or submit a ticket with the Service Desk or call us at (603) 646-2999.
Restore from Time Machine Backup
- Turn off the computer.
- Plug in the external drive with your Time Machine backup.
- Turn the computer on and hold the Command and R keys until a loading bar appears. If you have an M1 Mac, hold down the power button until you see "Loading startup options" and click "Options"
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- Select Restore from Time Machine.
- Select your Time Machine backup drive as the source.
- Select the date of the backup that you would like to restore to.
- Select your computer's hard drive as the destination and click Continue.
- This will take a while. Once it finishes restoring, your computer should be back on the old operating system with your applications and data intact.
If you have any issues, please submit a ticket with the Service Desk or call us at (603) 646-2999.