dotNetFx40_Full_x86_x64.exe /x:C:\temp\NET40_Extracted
Security and best practice
Technically, .NET 4.x versions are "highly compatible" and in-place updates. If you have .NET 4.8 installed, it usually handles apps designed for 4.0. However, some older enterprise software is hard-coded to look for the specific dotNetFx40_Full_x86_x64
If you manage multiple computers, you can download the offline installer once and use a USB drive to install it across all of them without wasting bandwidth. dotNetFx40_Full_x86_x64
: You can download it once and use a USB drive to install it on multiple machines without re-downloading. System Compatibility Supported OS dotNetFx40_Full_x86_x64