External Hard Drive Won't Mount

[acropoli]

I just bought a new external hard drive and was attempting to reformat it from ExFAT to APFS encrypted. The operation failed and now the disk won't mount (thought it still appears in Disk Utility). I have tried to reformat and use first aid but neither will work. Any help or suggestions are appreciated. There is not data on the drive so recovery of files is not an issue.

This is what it says when attempting first aid:

First Aid process has failed. If possible back up the data on this volume. Click Done to continue.
Details
Repairing file system.
Volume is already unmounted.
Performing fsck_hfs -fy -x /dev/rdisk3s1
File system check exit code is 8.
Restoring the original state found as unmounted.
File system verify or repair failed.
Operation failed…

This is what it says when attempting to reformat:

Erase process has failed. Click Done to continue.
Details
Unmounting disk
MediaKit reports not enough space on device for requested operation.
Operation failed…

 

[Superspeed500]

Have you tried to use another partition editor? Maybe GParted can help you? But be careful not to format or mess with the wrong drive!

 

[acropoli]

I had not tried that. But was finally able to resolve things. I tried clicking the "Restore" option in Disk Utility. There was an options called "Container disk 1." I used that, it still didn't work but I had some other options in Restore and did it a couple more times. That still didn't get it working but after doing that I was able to finally reformat the drive after booting into recovery. So not really a precise science here but it got the drive working.

 

[chscag]

I guess we should also ask.... why would you want to format an external hard drive to APFS encrypted? There is no advantage to doing that. Just format it as HFS+ and then encrypt it with FileVault.

And when you erase an APFS drive, you have to do it at the "container level". (As you already found out.)

 

[Fishrrman]

Agree with chscag above.

Don't use APFS on an external drive.
Use HFS+.
I predict things will go better that way.