Disk Utility First Aid reports errors on Mac

Symptoms

• First Aid reports finding and repairing minor errors
• First Aid fails to complete or reports it 'could not repair' the disk
• The same errors reappear after repeated First Aid runs
• Errors are accompanied by other symptoms like freezing or slow performance

Likely causes

• CommonMinor file system inconsistencies from normal use or improper shutdownsThese are usually harmless and get fixed automatically by First Aid.
• PossibleA drive with developing bad sectors or hardware wearPersistent, recurring errors can point to physical drive issues.
• PossibleRunning First Aid on the currently booted startup disk with limitationsSome repairs require running First Aid from Recovery Mode instead for full access.
• PossibleA severely corrupted file system needing a full erase and restoreThis is a more serious scenario, usually after major corruption.
• PossibleAn aging drive nearing end of lifeMechanical and even SSD drives eventually wear out after years of use.

What to do

1. If running First Aid from within macOS normally, note that some repairs require Recovery Mode for full access to the startup disk.
2. Restart into macOS Recovery (Command+R on Intel, or via startup options on Apple silicon) and run Disk Utility's First Aid from there instead.
3. Read the specific error message reported, since 'repaired successfully' is a good sign while 'could not repair' or repeated failures are more concerning.
4. Back up your important data immediately if First Aid reports it could not fully repair the disk.
5. Run First Aid a second time after a successful repair to confirm errors don't reappear.
6. Check the drive's overall health (via Disk Utility's info panel or a manufacturer's diagnostic tool) for signs of physical wear.
7. If errors persist across multiple First Aid attempts from Recovery Mode, consider backing up fully and reformatting the drive as a more thorough fix.
8. If reformatting doesn't resolve recurring errors, the drive itself is likely failing and needs replacement.

Tools and parts

• None required

When to call a pro

If First Aid can't repair the disk even from Recovery Mode, back up what you can and have a professional assess whether the drive needs replacement.

Safety