If you are on a newer Mac, you can sometimes use the Terminal command:

Beyond a standard installation, macOS High Sierra 10.13.6 holds significance for specific user communities.

However, as of November 2020, High Sierra is no longer officially supported and does not receive security updates.

High Sierra was a "refinement" update, focusing on under-the-hood performance rather than visual overhauls.

The final update — 10.13.6 — includes security patches, stability improvements, and support for AirPlay 2 multi‑room audio in iTunes, along with enhancements to Photos and Mail.

Expired certificate. Apple’s signing certificate for High Sierra expired in October 2019. Solution: Open Terminal and set the system date back to when the certificate was valid:

This downloads the installer directly to your Applications folder without needing the App Store.

(Sets date to Jan 1, 2018) . Then run the installer. After installation, reset the date with sudo sntp -sS time.apple.com .

A solid‑state drive (SSD) is strongly recommended, as High Sierra’s APFS file system is optimized for flash storage.

Open and restore the DMG file to your USB drive.

Released in July 2018, the was the final major stability update for High Sierra. It is widely considered the "most mature" version of that OS generation, providing significant enhancements in security and stability over the initial 10.13 release. Key Features of 10.13.6:

Incompatible firmware or corrupted DMG. Solutions:

Name the drive Untitled , set the format to , and choose GUID Partition Map . Click Erase. Open Terminal and paste the following command:

For testing or running legacy applications, High Sierra is often installed in virtual machines using software like VMware or VirtualBox . For these purposes, an .iso file is usually required instead of a .dmg . You can create a bootable .iso from a .dmg installer using the Terminal, which can then be used to set up a virtual Mac environment.