The download link for High Sierra takes me to System Preferences and tells me the download is not available.
I'm trying to build and installer on a USB stick to reinstall High Sierra OS on an older iMac that was previously set up with Linux. I want to turn it back into a Mac. The link in Apple Support article does not work. It takes me to the App Store, and the 'Get' button opens System Preferences 'Software Update' pane. I'm not able to download.
How to get old versions of macOS - Apple Support
iMac, OS X 10.11