Figured it out...
My administrator password was blank, but sudo commands in the terminal won't work with a blank password. I changed the password temporarily and the terminal accepted that. Problem solved!
Next question - do you know of a good pr…
I wonder if completely removing your Apple ID from a machine after updating to Sierra would render the install "clean" - unless they bake that ID into the install
Thanks a ton John, as always your answers are incredibly thorough. I'll definitely test out your method with an external drive and SuperDuper since you're not noticing a bottleneck.
Regarding OS versions, which ones do you keep images of? I'm assum…