At one time, when I would go to the App Store, the previous versions of OS I downloaded would appear (e.g. El Capitan, Mavericks, etc.) However, none of these are listed there anymore - although the link provided earlier (#48653) says that older versions should appear in one's Apple Account under "Purchased."
If I go into Recovery, the only option is Sierra, which I currently have installed.
So, if Bob is still looking for FULL "El Capitan" (not just updates), where does he find it to download and install if not previously saved on a separate drive?
I don't know why you're not seeing anything in your Purchased tab; I've still got Yosemite and El Cap available for d/l in mine. (El Cap is the last version of macOS that would show in "Purchased"...something to do with transferring Macs between owners if my memory serves me.)
As per How to reinstall macOS - Apple Support
, Recovery offers three options, depending on which key combo you use to access it.
I thought Bob would be able to d/l El Cap via How to download OS X El Capitan - Apple Support
(I think grelber did.), but I just digested it and saw
OS X El Capitan remains available for Mac computers that can't upgrade to macOS High Sierra, or that need to upgrade to El Capitan first.
which suggests that he can't, because his MBP is High Sierra capable.
I dunno. Let's see if he can wangle it out of AppleCare, and if not, he may have to go to eBay, which may be cheaper than upgrading his software. (Hmmm... In a pinch, I could d/l El Cap [which I just did, as a matter of fact, to make sure I could], burn it to a DVD, and mail it to him.)
[rant] Damn! Wanting you to be current is reasonable, but forcing you to be current, particularly when it's going to cost you, is NOT.
I don't get it. I don't doubt that Apple supports the Business Software Alliance, so why do they at the same time, in effect, support a market for bootleg OS X/macOS? [/rant]