I am using VS 2015.
Your project is not referencing the \".NETFramework,Version=4.5\" framework. Add a reference to \".NETFramework,Version=4.5\" in
I actually just figured out the problem. I ended up clicking on Restore Nuget Packages at the solution level and I managed to compile my PCL file, and then the rest of my solution.
Restore Nuget Packages
PCL
Hope this helps.