Report: Downloading and Installing macOS Sierra 10.12 from a DMG File

  1. Connect a 16GB USB drive to your Mac. Name it "MyVolume" for ease of use.
  2. Open Terminal (found in Applications > Utilities).
  3. Type (or copy/paste) the following command exactly: 
    sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ macOS\ Sierra.app
  4. Type your administrator password and press Enter.
  5. Type Y to confirm erasing the USB drive.
  6. Once the process says "Install media now available," you have a bootable installer.

Because Apple hides older installers in the "Purchased" tab or removes them from the main App Store search, finding the DMG file can be difficult. Here is the step-by-step process to download the file and create a bootable installer.

Report ID:

TEC-MACS-1012-001 Date: [Current Date] Prepared For: Users requiring legacy macOS installation methods

Browser Recommendation

: It is highly recommended to use Safari for the download, as other browsers like Firefox or Chrome may occasionally fail to process the disk image correctly. Preparing the Installer