A:Answer In most cases, Windows S mode only allows the installation of programs from the Microsoft Store. To install Norton 360, you will have to get out of S mode, and there will be a warning about doing so. This information comes from a community on Norton: "S mode restricts apps you can install on your device to those available in the MS Store. If you find that the S mode is too restricting, here is a MS Support article on how to disable S mode. But it is a one way move".