Find the disk to repair using: diskutil list Make a note of the disk you want to work with (in the IDENTIFIER column) The disk name will be in this form: /dev/diskID For example: /dev/disk3s1
To verify the disk, type: diskutil verifyVolume /dev/diskID Where /dev/diskID is the ID you identified above the verify might take a while. When complete a message stating if everything is OK will appear, or it might say repair is necessary.
To verify a disk instead of a volume, use the verifyDisk option instead
To repair a volume, use: diskutil repairVolume /dev/diskID To repair a disk, use the repairDisk option. Note that you cannot repair the boot disk, boot form another disk first.
My latest blog post: Think for Yourself: In the end, everything is just an opinion. Be skeptical, and think for yourself! (posted 2026-04-25).
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