docs/includes/net-framework-4x-versions.md

[!IMPORTANT] All .NET Framework versions since .NET Framework 4 are in-place updates, so only a single 4.x version can be present on a system. In addition, particular versions of .NET Framework are preinstalled on some versions of the Windows operating system. This means that:

• If there's a later 4.x version installed on the machine already, you can't install a previous 4.x version.
• If the OS comes preinstalled with a particular .NET Framework version, you can't install a previous 4.x version on the same machine.
• If you install a later version, you don't have to first uninstall the previous version.