High Sierra installer still available?
I needed to re-install a clean copy of High Sierra on an older Mac that does not have internet access. I didn't try the recover volume because I thought it required networking. (Probably should have tried it anyway.) But I still have a copy of the "Install macOS High Sierra" app but running it gave me the "application is damage and can't be used to install" error. It's my understanding that this is caused by an expired certificate.
I tried searching for High Sierra in the app store (on my Catalina Mac) but nothing showed up. So I found a direct link which ended up opening the High Sierra page in the App Store app. I clicked the "GET" button which then then runs Software Update and I get an alert saying "Update not found - The requested version of macOS is not available." I seem to recall the "GET" button changing to "Download" when pressing the option key or something but that doesn't seem to work anymore.
Anyway, I went with the "set the clock back to 2014" kludge and was able to install High Sierra.
But my question is: Are older *working* macOS installers for older Macs actually no longer available? Or can you just not download them with a Mac running Catalina? (I have High Sierra in a VM, so I guess I could try that at some point...) Or am I just looking in the wrong place?
iMac Line (2012 and Later)