Xamarin UWP project is not being built after creating in Visual Studio 2015

Question

I installed Xamarin for Visual Studio 2015 and I created Xamarin.Forms Portable project. After that I have tried to build solution.

But I got an error for UWP project: Error Type universe cannot resolve assembly: System.Runtime, Version=4.0.0.0, in Visual Studio 2015.

What is the problem?

Answer 1

The solution was simple. I installed Mirosoft.NETCore.UniversalWindowsPlatform package via the Package Manager Console:
PM> Install-Package Microsoft.NETCore.UniversalWindowsPlatform