how to find software update
How do I update my Mac ios version to the latest.
iMac 27″ 5K, macOS 10.13
Question marked as
In 10.13 you use the App Store.
Or...
Try installing this in Safe Mode, but not using Firefox...
https://itunes.apple.com/us/app/macos-mojave/id1398502828?mt=12
Safe Boot, (holding Shift key down at startup).
