It looks like I have to update the OS on my old machine to use TeamViewer, else I can’t remote to my clients for a week.
I looked on my backups and I have the Mountain Lion install (currently running SL on a 2008 unibody).
I have 3 copies of this install, and none will run. They all say they are damaged and that I need to download again. It directs me to the App Store, where I do see ML way down at the bottom.
However, I know I also downloaded Sierra and High Sierra, but they are not on the list at all.
First question - how can I protect the downloads I have so they continue to run?
Second - where did my Sierra installs disappear to? I do have backups of those too but now I’m afraid they won’t work if I ever need them.
I seem to recall that Apple had a signing issue with their installers at some point in the last year or two, so maybe that’s why your previously downloaded installers don’t work? (See https://tidbits.com/2016/03/02/previously-downloaded-os-x-installers-no-longer-work/ )
Apple’s support pages suggest that you can get Sierra, High Sierra, or El Capitan on the App Store. See https://support.apple.com/en-us/HT208202 and https://support.apple.com/en-us/HT206886
You have to use the links in the support pages @ddmiller linked to in order to download previous OS installers. You won’t get to them through browsing or searching the App Store.
The certificates for the OS installs on older versions expired. Apple hasn’t updated most versions (I forget the where the cut off is), so even if you do download them again, they won’t install. To install an old version, set the Mac’s clock back a few years, then remember to to set it back to current time when done (that’s the hard part!)
Second question first: Your Sierra installs “disappeared” because, for some reason, the App Store no longer lists macOS installers in the Purchased list, starting with Sierra. It’s not you, it’s them.
First question second: I assume that by “protect the downloads” you mean you want them listed. While you can’t put them back in the Purchased list, you can still access them: With the Purchased list displayed, type “macos” in the Search field in the tool bar (or “sierra” or “high sierra”) and choose from the dropdown menu of matches.
(Believe it or not, I just ran across this info in the last couple of days while researching details for an article about the App Store. Synchronicity!)
The machine you are on does not support High Sierra, right? So the Mac App store will not show it to you. Even if you go to the direct links you will not be able to download it via the MAS on a machine that will not run it.
If you did not “purchase” Sierra at the time it was current, you can’t download it either (from the MAS), however, as @ddmiller said, you can download it using the link posted on the support pages. This has even gotten better (I am able to download Sierra on a machine running High Sierra via that link which was not possible last time I looked).
Thanks everyone, especially for bumping the thread as I hadn’t seen any of these.
I think the unibody supports Sierra, but definitely not High Sierra.
Date change is easy - if I can remember it! I have to mess with the machine again now that my MBP is back in my hands. So if I change the date, the ones that failed should work again? I will try this on the ML install I have.