Oct 24, 2012 - With Windows 8/10,.NET Framework 4.5 comes installed by default. Since.NET 4.5 is an in-place upgrade of 4.0, you can automatically run. The Microsoft.NET Framework 3 is the new managed code programming model for Windows®. It combines the power of the.NET Framework version 2.0 with new technologies for building applications that have visually compelling user experiences, seamless communication across technology boundaries, and the ability to support a wide range of business processes.