See my post at:
Windows 2012 and 2012R2 come with .NET 4.5.
Microsoft apparently sees .4.x as being 4.0 in some places, like in directory C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\. as mentioned in Rebuild the Orion Website - SolarWinds Worldwide, LLC. Help and Support . There is no C:\Windows\Microsoft.NET\Framework\v4.5 even on a system with 4.5 installed.
In other places on Windows 2012 and 2012 R2, such as Server Manager, it sees .NET 4.6 as being 4.5.
I think all of this is a sign that programmers and managers at Microsoft abuse recreational drugs, and cannot think past today.