Microsoft does not provide a single ISO file for Visual Studio 2019. Instead, you must create a "local layout" using a command-line tool. This allows you to download all necessary files onto one machine and transfer them to another that has no internet access Stack Overflow Step 1: Download the Bootstrapper
Notably, Visual Studio 2022 introduced improvements to the layout command (such as --fix for corrupted layouts), but the core concept is identical. The lessons learned from maintaining 2019 offline layouts directly apply to 2022 and beyond. visual studio 2019 offline installer
Cause: You tried to install directly to a network drive or USB drive as the destination for Visual Studio itself. Fix: Visual Studio cannot run from a network drive. The offline layout must be on a local drive (C:\ or D:). Copy the layout from USB to the local machine, then install. Microsoft does not provide a single ISO file
Use the same --layout command on your original online PC. GUI: run vs_installer
The installer compares your local folder with Microsoft’s servers and downloads only the changed files.