Build #?
the author says to click on "version." But even in his screenshot there is no "version" button.
He might mean to click on "more info..." When I did I got a bunch of info including this
Software OS X 10.8.1 (12B2080)
I think the # in parentheses is the build number.
Mac mini, OS X Mountain Lion (10.8.1), Info relating to update problems
