(or disk image) is a single file that contains the entire contents of an optical disc Microsoft 365 , this format allows users to: Install Offline
: Unlike the web installer, which always grabs the absolute latest build, an ISO captures a specific point-in-time version. This is helpful if you need to ensure compatibility with specific third-party plugins that might break on newer updates. The "Hybrid" Catch : Even with an ISO, Microsoft 365 is still a subscription. You will still need to sign in with a Microsoft account