If the solution is created by Xamarin, I get the following error message opening it with VS2013 pro:
The projects created by Xamarin Studio should be compatible.
If I create a C# console project in Xamarin Studio 5.9.4 I can open that in Visual Studio 2013 on Windows.
The error that Visual Studio is showing about "Project target framework not installed" and then a strange error saying it cannot find .NETFramework,Version=v4.5 and then offering to convert the project to .NET 4.5 looks like a Visual Studio problem. It is as though Visual Studio cannot find .NET 4.5. Can you create a .NET 4.5 project in Visual Studio 2013?
A quick google search for that error shows a few results where it seems to be a problem with the Visual Studio installation.
Thanks, it was it. Solved after repairing my VS installation.
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