Steps to repair a disk with Disk Utility:
- Apple silicon: Turn on your Mac and hold down the power button until the startup choices window appears. Then click Continue after clicking the gear icon labelled Options.
- Processor Intel: Turn on your Mac, then press and hold these two keys until an Apple logo or other picture appears: R () and Command ().
- You could be asked to choose a user for whom you know the password. After selecting the user, click Next and type in their administrator password.
- Select Disk Utility from the utilities menu in macOS Recovery and click Continue.
- In Disk Utility, select View > Show All Devices (if available) from the menu bar or toolbar.
- Start by picking the last volume on each disc you're repairing, then clicking the First Aid button or tab.
- To begin checking for faults on the specified volume, click Run.If the Run option isn't available, select Repair Disk instead.
- Skip this step for the disc, container, or volume you selected if the button is dimmed and you can't click it.
- Enter your administrator password if prompted for a password to unlock the drive.
- After Disk Utility has finished examining the volume, go to the sidebar and choose the next item above it, then run First Aid again. Continue working your way up the list, performing First Aid on each volume, then each container on the disc, and ultimately the disc itself.
- Disk Utility should now be closed. You can now restart your Mac if you used Disk Utility from macOS Recovery: select Restart from the Apple menu.
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