dotnetfx.exe /c:"msiexec.exe /a netfx.msi TARGETDIR=C:\DotNet" Extract SP1: dotnetfxsp1.exe /Xp:C:\DotNet\netfxsp.msp Merge them: msiexec.exe /a C:\DotNet\netfx.msi /p C:\DotNet\netfxsp.msp Run the resulting to install. Microsoft Learn Important Considerations
: Most legacy apps designed for 1.1 or 2.0 can run using .NET Framework 3.5 , which is included in Windows 10/11. Open Control Panel > Programs and Features . Select Turn Windows features on or off .