I recently purchased a second-hand 2015 13" MacBook Pro. It came with High Sierra installed, but I wanted to make sure the system was completely clean (in case it had been compromised), so I:
- Booted into internet recovery mode by restarting and pressing ⌘⌥R.
- Used Disk Utility to erase the entire internal drive. Unlike the internal recovery partition, internet recovery did not allow me to format it as APFS, so I chose HFS+ Journaled instead.
- Attempted to use the "Reinstall OS X" option to do just that.
The installer was for Yosemite; that would be just fine with me (I can upgrade later). After clicking through the licence agreement, selecting the target drive, and clicking "Install" I was prompted for my Apple ID and password to log into the app store, after which I received the following error message:
This item is temporarily unavailable. Please try again later.
(Needless to say, trying again later has not helped.)
I am pretty sure the problem is that I never "purchased" Yosemite; by the time I went to install it on a previous machine only El Capitan was available in the app store, and unfortunately there seems to be no way to retroactively "purchase" Yosemite, which is a bit of a problem in this case.
How can get macOS installed on this machine again—ideally without needing another machine (both because it is inconvenient, and because of the risk that the other machine might be compromised)?
(I am not too fussy about which version I get, since I probably want High Sierra in the end and can upgrade easily enough.)