I used the recommended link to download an older version MacOS
https://support.apple.com/en-us/HT211683
On the app store, when I tried to open the Mojave link, an alert said this.
This copy of the Install macOS Mojave application is damaged, and can‘t be used to install macOS.
Seeking help to upgrade from MacOS Sierra but still running a critical 32-bit application.
MacBook Pro 15″, macOS 10.12
That message actually means that the App Store has detected a copy of Install macOS Mojave.app
in your Applications folder.
Locate it, move it to the Trash, empty the Trash.
Connect your mac to your router via cable, restart your mac.
Go back to the App Store Mojave page it will now say Get or Download,
not Open as before, see screenshot.
Do not use the mac while it is downloading or any other devices that share the same internet connection.
That message actually means that the App Store has detected a copy of Install macOS Mojave.app
in your Applications folder.
Locate it, move it to the Trash, empty the Trash.
Connect your mac to your router via cable, restart your mac.
Go back to the App Store Mojave page it will now say Get or Download,
not Open as before, see screenshot.
Do not use the mac while it is downloading or any other devices that share the same internet connection.
Delete "Install macOS Mojave" from the Applications folder. Try again while in Safe Mode.
Just don't stream movies or other high usage items while the mac is downloading.
The image on the website is fine.
Whoa! Do not use any other devices that share the same internet connection? I don't think that is possible. At best, it actually means finding the fuses to turn off physical appliances, thermostats, etc. Sone have battery backup. Is that really a requirement to change Operating Systems?
Downloaded again after restart. Same result. Is it possible that the image on the web site is corrupted?
Updating a machine to Mojave, link on Apple site damaged?
