TEC-MACS-1012-001 Date: [Current Date] Prepared For: Users requiring legacy macOS installation methods
), extracting the installer application, and then using that to either upgrade your system or create a bootable USB drive. Apple Support Official Download & Installation Steps Download the DMG : Use Safari to download the official macOS Sierra 10.12 disk image directly from Apple Support. Extract the Installer Double-click the downloaded macOSSierra.dmg to open it. InstallOS.pkg download macos sierra 1012 dmg file install
The DMG file does not install the OS directly; it contains a package that installs the installer app into your Applications folder. extracting the installer application