While Microsoft provides an online installer for 3D Viewer, some users may not have a reliable internet connection or prefer to install software without an active internet connection. This is where the offline installer comes in – a self-contained package that includes all the necessary files for installation, eliminating the need for an internet connection.
In the "Shop" tab, type "3D Viewer." The app by Microsoft Corporation will appear. microsoft 3d viewer download offline installer
This is the most common method to grab the .appxbundle file directly from Microsoft’s servers for offline installation: While Microsoft provides an online installer for 3D