If that doesn’t work, back up as much of your data as possible, reformat the disk, reinstall macOS, then restore your backed-up data. If Disk Utility can’t repair your disk, or you receive a report that the First Aid process failed, try to repair the disk or partition again.If it contains information you need, open it and examine its data to make sure it hasn’t been corrupted.If you can replace a file or re-create it, delete it.Most of the files in the list have aliases in a DamagedFiles folder at the top level of your disk. You need to check each file in the list of affected files. If Disk Utility reports “overlapped extent allocation” errors, two or more files occupy the same space on your disk, and at least one of them is likely to be corrupted.Otherwise, you may need to do one of the following. You can click Show Details to see more information about the repairs. If Disk Utility reports that the disk appears to be OK or has been repaired, you’re done.If Disk Utility tells you the disk is about to fail, back up your data and replace the disk-you can’t repair it.

In the sidebar, select a disk or volume, then click the First Aid button .If you check your startup volume (Macintosh HD), make sure you also check your data volume (Macintosh HD - Data). Note: If you’re checking your startup disk or startup volume, restart your computer in macOS Recovery, select Disk Utility in the macOS Utilities window, then click Continue.In the Disk Utility app on your Mac, choose View > Show All Devices.If you run First Aid on a volume, Disk Utility verifies all the contents of that volume only. If you run First Aid on a disk, Disk Utility checks the partition maps on the disk and performs some additional checks, and then checks each volume. Disk Utility can’t detect or repair all problems that a disk may have. Repair a storage device in Disk Utility on Macĭisk Utility can fix certain disk problems-for example, multiple apps quit unexpectedly, a file is corrupted, an external device doesn’t work properly, or your computer won’t start up.

Wipe and reinstall mac os disk utility