How to recover a corrupted external exFAT hard drive

Solution 1:

I think the drive is already unmounted, if not then unmount it and do this

try mounting in read only mode by doing this

diskutil mountDisk readOnly /dev/disk2s1 

Check if the drive is hijacked by the system

ps aux | grep fsck

If you see your disk there hijacked then use this to kill this process

sudo pkill -f fsck

You should immediately see your drive at the finder's sidebar.

Solution 2:

I had the same issue before with my 4TB Seagate external hard drive too. It also takes too long for the system to recognize my disk, and a lot more issues came with it.

If you unplugged your drive without unmounting / ejecting it properly, it could potentially been occupied by some processes such as quicklookd in the background, this can potentially cause problems like corruption in the file system or corruption in clusters. But, if you were not making any modifications to your data at the time when you “unexpectedly” unplugged your drive, the data may not be affected, it’s just the file system is unrecognizable for your Mac temporarily since it could be broken when you unplugged your drive.

Here’s the trick, it worked like a charm to me every time when I unexpectedly unplugged my drive without properly ejecting it:

diskutil list # to see the identifier of your drive
# disk2s1 will be used in this example, replace it with your own drive identifier
sudo fsck_exfat -y disk2s1