Part 1: Official macOS Sierra 10.12 DMG Direct Download Links

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/SierraInstaller --applicationpath /Applications/Install\ macOS\ Sierra.app Use code with caution. Press .

If the official method fails or you cannot access Apple's website, dedicated third-party utilities offer a more reliable way to download a .

Once the InstallMacOSX.dmg file sits in your Downloads folder, you must convert the raw payload into a functional app file.

Your Mac will restart automatically and begin the update process. Part 6: Troubleshooting Common Installation Errors

Once you've found a reliable source, click on the download link to obtain the macOS Sierra 10.12 DMG file. The file size is approximately 5.2 GB.

Open from the Utilities drop-down menu at the top of the screen.

To create a bootable installer, you'll need a USB drive with at least 8 GB of free space. You can use the createinstallmedia command in Terminal to create a bootable installer:

Warning: macOS Sierra (10.12) is an older release. If your Mac supports a newer macOS, prefer the latest supported version for security and app compatibility. The steps below assume you understand the risks of running older system software.