How to Run Disk Utility First Aid on macOS

Use Disk Utility to diagnose and repair disk errors on your Mac. Follow these steps to restore file system integrity and resolve boot issues.

1. Open Disk Utility. Press Command + Space to open Spotlight Search. Type 'Disk Utility' and press Enter to launch the application.
2. Show all devices. Click the View button in the top-left toolbar. Select 'Show All Devices' from the dropdown menu to ensure all volumes and containers are visible in the sidebar.
3. Select the target disk. Select your disk or volume from the sidebar list. Begin with the bottom-most item in the hierarchy, such as 'Macintosh HD', then work your way up to the parent container.
4. Run First Aid. Click the 'First Aid' button in the toolbar. A confirmation dialog will appear; click 'Run' to initiate the diagnostic scan.
5. Review the repair results. Wait for the process to complete. Disk Utility will display a report indicating whether errors were found and successfully repaired, or if manual intervention is required.
6. Quit the application. Click 'Done' once the summary is displayed. Close Disk Utility by pressing Command + Q.