Compatibility and warnings

Use Apple’s built-in createinstallmedia tool inside the downloaded app to write the High Sierra files onto the newly mounted volume:

Your Mac will open the panel (or App Store purchase history) and begin downloading the file.

The preference pane will open. Confirm the download.

How to Download macOS High Sierra 10.13.6 DMG on Mac If you need to revive an older Mac, set up a virtual machine, or create a bootable installer, finding a reliable, official download for is critical. Apple no longer displays this older operating system prominently in the Mac App Store, making it tricky to locate.

To boot from this drive, shut down the target Mac, plug the USB in, hold down the key, and turn the Mac back on. Select the High Sierra installer from the boot menu screen.

That creates a HighSierra.dmg on your desktop.

This guide is intended for legitimate use cases, such as running legacy software, repairing an older Mac that requires this specific version, or testing applications in a virtual machine. Always ensure you have a legal right to install the software and prioritize data safety by backing up your system.