folder before you can install it or create a bootable drive. Open the DMG : Double-click the downloaded InstallOS.dmg Run the PKG : Inside, you will find a file named InstallOS.pkg . Double-click this and follow the prompts. This does install the OS; it installs the "Install macOS Sierra" app /Applications Apple Support Community 3. Installation Methods Direct Installation
Now that you have a bootable installer, you can proceed with the installation: download macos sierra 1012 dmg file install
If your macOS is too old to support that command, use this direct link (copy into a web browser): http://updates-http.cdn-apple.com/2019/cert/061-41343-20191023-3a5f1b2c-5e6f-7d8a-9b0c-1d2e3f4a5b6c/InstallOS.dmg folder before you can install it or create a bootable drive