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Scan a Disk for Bad Blocks

You can use terminal to check a disk for bad blocks (physically damaged areas of the disk).

First find the name of the disk, run:
diskutil list
And make a note of the disk name, eg disk8

After finding the disk name, run:
sudo fsck_hfs -fy -S /dev/DISKNAME
Enter the admin password and let the check run.

Note: This process does not guarantee that it won't make the damage worse, but this applies to all processes of this type.





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