If the DMG search fails, consider these legal alternatives:
Double-click the downloaded InstallmacOSX.dmg file to mount it.
Depending on your goal, you have two primary ways to proceed: How do I install MacOS Sierra DMG to Bootable USB? download macos sierra 1012 dmg file install
Downloading and installing macOS Sierra 10.12 involves a specific sequence of actions, as Apple now provides older operating systems as disk images rather than direct App Store downloads for modern Macs Apple Support 1. Downloading the macOS Sierra DMG
You will need an empty USB flash drive with at least 8GB or 16GB of free space. If the DMG search fails, consider these legal
Open the system application ( /Applications/Utilities/Terminal ).
Now that your bootable media is prepared, you can proceed to install the operating system. Booting from the USB Drive Shut down the target Mac completely. Downloading the macOS Sierra DMG You will need
This is the most frequent roadblock users face when deploying older versions of macOS. It happens because the digital security certificates embedded within the 2016 installer file have since expired.
Open Safari and navigate to the official Apple Support page for old macOS versions. Scroll down to the "macOS Sierra 10.12" section.
Here is the safe, official method to download the (or installer app) and create a bootable USB.
Locate the hyperlink. Clicking this starts a direct download for a file named InstallOS.dmg .