DiskUtility throwing "com.apple.disutility error 3" on "Operation failed with status 5" on Sierra while making image backup of main SSD On a MacBook Air running Sierra, I'm trying to create an image backup from my main SSD to an external USB disk using a clean shutdown, then during start: Command-R -> Disk Utility.

Both the main SSD and USB HDD get through "first aid" fine.

I'm not using file vault.

It fails right at the end (after the progress bar has been fully blue).

My Google tries all fail to return meaningful results:


https://www.google.com/search?q="disk+utility"+"error+3"+"status+5"
https://www.google.com/search?q="disk+utility"+"error+3"
https://www.google.com/search?q="disk+utility"+"status+5"


The only result is from someone trying to create an ISO image from an optical disk: https://discussions.apple.com/thread/7663155?start=0&amp;tstart=0

This is the screen during backup (sorry for a non-PNG one: when in Command-R mode, I could not find a way to make a proper screenshot).

On a Retina MacBook Pro with Yosemite this works perfectly fine.
I just experienced the same problem while trying to clean install Sierra. I had the same error until I asked Disk Utility to mount the internal SSD. When I did so, it asked for the password to unlock the drive. After unlocking the drive, I was able to create the disk image.