To convert that USB into a DMG file (for archival):
If you already have Yosemite installed and need to update to the final version, download the OS X Yosemite 10.10.5 Combo Update How to Install from a DMG Use Safari to download the file to your Double-click the file to open it. This will mount the image and show a (package) file. Run Installer: Double-click the
First, I know that macOS Yosemite is an older version, released in 2014. The specific version they want is 10.10.5, which is a later update. They might need this for compatibility reasons, maybe for an old app or hardware that doesn't support newer macOS versions.
: Double-click the .pkg file and follow the onscreen instructions. This does not install the OS yet; it installs the official installer into your Applications folder .
: Open your Applications folder and double-click the installer app to begin the process. Create a Bootable USB : If you need to perform a clean install, use the createinstallmedia command in Terminal with a formatted 12GB+ USB drive.
: Inside the mounted image, double-click the .pkg file (e.g., InstallMacOSX.pkg ).
Possible steps for the user: