App compatibility collapse
Installation issues with DMG
Not recommended for primary machines
Before we dive into the download process, let’s deconstruct why users are specifically hunting for version 10.13.6 on a new DMG.
Apple released Security Update 2020-006 for High Sierra in November 2020. That is the last one. When you install a "new" DMG from 2018, you must run Software Update and install: macos high sierra 10136 dmg new
Note: As of 2026, no new security patches come out. Use a modern firewall and avoid logging into sensitive banking on this OS unless isolated.
Issue 1: "This copy of the Install macOS High Sierra application is damaged" App compatibility collapse
Issue 2: "Can't be verified because it was not signed"
Issue 3: The DMG is only 24MB, not 5GB+
Let’s be realistic. For daily driving, yes. You cannot use iCloud Drive advanced features, Universal Control, or the latest Xcode. However, for these specific use cases, 10.13.6 reigns supreme: