Before clicking the download button, it is crucial to understand why you should choose this specific version over newer editions.

When you run the standard vs_professional.exe bootstrapper without specifying a version, it usually defaults to the latest recommended release. To get version 15.9 specifically, you cannot simply click a large "Download" button on the main landing page. You must utilize the specific "Redistributable" or "Bootstrapper" links provided in the Visual Studio documentation archives.

If you are working on a project started in 2017, opening it in Visual Studio 2019 or 2022 might trigger upgrade prompts, changes to the .sln file, or modifications to the C++ toolset. For teams that cannot risk changing a compiled binary’s behavior, sticking to the exact environment used during development is non-negotiable. This makes the a frequent requirement for maintenance contracts in banking, government, and healthcare sectors.

This is the method for most users with a reliable internet connection. You need the specific executable that targets the release channel for 15.9.