Even if you find a clean DMG, High Sierra has a notorious “Gatekeeper” issue. Because the certificate on the installer expired in 2019, macOS will flag any copy downloaded today (even from Google Drive) as “damaged.” You have to manually change your system date in Terminal to install it. Most Google Drive copies do not include these instructions, leading to hours of frustration.
The 10.13.6 release was the final major update for High Sierra, known for refining the "under-the-hood" changes introduced in version 10.13.
sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Installer Use code with caution. Copied to clipboard
Apple’s official “Purchased” tab only shows older installers if you downloaded them before. Google Drive provides a high-speed, resume-friendly download for IT pros and hobbyists.