sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

This article serves as the definitive resource. We will cover everything from legal download sources and DMG verification to step-by-step installation guides and solutions to the most common errors (such as “This copy of the Install macOS High Sierra application is damaged”).

To install High Sierra on a fresh hard drive or a different Mac, you must flash the installer onto a physical USB drive. Prerequisites A USB flash drive with at least of capacity.

Apple ended official support for macOS High Sierra on November 12, 2020 . This means the OS no longer receives any security updates. Any new vulnerabilities discovered since that date remain unpatched, putting your system and personal data at significant risk if used for daily activities on the internet.

Press the button while holding down the Option (Alt) key. Release the key when the Startup Manager screen appears.

Open and paste the following official Apple command:

A DMG file is a mountable disk image used to distribute software on macOS. In the context of the OS installer:

Similar to the damaged application error, this points to a time mismatch between your computer hardware and Apple’s verification servers.

The macOS High Sierra 10.13.6 DMG remains a vital tool for IT administrators and vintage Mac enthusiasts. While the App Store provides the official installer application, converting this to a DMG or acquiring a pre-made bootable image is standard practice for virtualization and offline system recovery.

Install the OS on multiple Macs without downloading it every single time.

The drive will be formatted, so ensure any important files on it are backed up. Step-by-Step Instructions Plug your USB drive into your Mac.