Testing a portable library between .Net 4.6 and Windows Universal 10.0

I coded a portable class library that targets .NET Framework 4.6 and Windows Universal 10.0, which uses some System.Reflection; methods:

• Type.GetProperty
• PropertyInfo.GetValue

To test my methods I coded a test library that targets .NET Framework 4.6. All the methods that don't use System.Reflection; are tested correctly. If, from the test library I call a method that uses one of the methods above, I get this error:

How can I solve it? What am I doing wrong?