The safest and most reliable way to download macOS High Sierra is directly from Apple. While it may not appear in the Mac App Store "Featured" section anymore, Apple keeps the link active in their knowledge base.
Once you have the file, most users want to create a bootable USB drive for a clean installation. Plug in a USB drive (at least 16GB). Rename the drive to "MyVolume".
The safest way to get the DMG is directly from Apple. Follow these steps: download macos high sierra 10136 dmg mac top
Before downloading, ensure your Mac is compatible. High Sierra generally supports the following: At least 2GB (8GB recommended for better performance). Storage: Minimum 14.3GB of available space for the upgrade. Models: MacBook (Late 2009 or newer) MacBook Pro/Air (Mid 2010 or newer) iMac (Late 2009 or newer) Mac mini (Mid 2010 or newer) How to Create a Bootable USB
If you have an old Install macOS High Sierra.app in your Application folder, delete it, empty the trash, and try the download link again. Conclusion The safest and most reliable way to download
Revive a Mac that cannot boot into Recovery Mode or has a corrupted drive.
Select and follow the on-screen configuration prompts. Plug in a USB drive (at least 16GB)
Type or paste the following command exactly as shown: softwareupdate --fetch-full-installer --full-installer-version 10.13.6
If you do not have access to a Mac to create the installer, you may need to download a pre-packaged DMG from a reputable software archive.