How do I fix corrupted and unreadable external hard drive Mac?

Fixes to ‘The disk you inserted was not readable by this computer’ error

1. #1. Plug in Different Device to Mac.
2. #2. Check File System of Inserted Disk.
3. #3. Repair Unreadble Disk with Disk Utility.
4. #4. Initialize Disk and Recover Data.

Aug 11, 2021