Downloading High Sierra to a Mojave-capable iMac

Question

I have a late 2014 iMac that is running Yosemite and is ccompatible with Mojave. But I want to upgrade the OS to High Sierra, not Mojave.

How do I do this?

Answer 1

If you're in the US, go to this link.

Note: Links to all macOS downloads from Leopard to Mojave are listed on this page at Krypted.com.

Answer 2

I needed to do something similar recently, and I found the downloaded High Sierra I had saved was corrupt in some way, and I re-downloaded via the App Store…which gave me a stub installer (about 20MB) rather than the full 5.7GB version.

The way I found to force the full download from Apple was to use High Sierra Patcher Tool from dosdude1.com -- download it, unzip the archive, run the app inside (you will likely need to right-click -> open as the developer is not recognised). Ignore all the stuff about patching your system, clear any dialogs about your system already being supported (if they appear and choose Tools -> Download macOS High Sierra…:

The patcher app will ask you for confirmation:

Select Yes and it will start downloading the full installer:

At the end of this process, you'll have a working self-contained High Sierra installer. The patcher will ask if you want to make a patched USB installer -- answer Not now to this:

Locate the download in your chosen folder, and you should have a 5.7GB portable installer:

After you've installed High Sierra, you can change the macOS update settings to defer (possibly indefinitely, to be confirmed) the Mojave installer auto-downloading using System Preferences -> App Store -> uncheck Install macOS updates:

You can opt-in to any updates when you're ready.