Originally Posted By: plantsower
I am assuming we are still in the external HD?

You want to be booted into Sierra 2015 Macintosh HD on your internal SSD with your external HDD connected when you run the command.

Technically, you could also run it while booted into a bootable partition on your external, but since your external is suspect, let's avoid using it and stick to your REAL OS, i.e. the one on your internal.

Last edited by artie505; 04/24/20 12:43 AM. Reason: Complete rewrite
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