Ok as we all know in OO programming one should program to the interface or to the abstract/base class. I have created a service which has two methods one returning an instance of the base class and another returning an instance of a concrete class that inherits from the base class.
To call these service methods, I created a client application. The service method returning an instance of the base class works but the method returning an instance of the class which inherits from the base class doesn't (some sort of communication error or so it claims). I tried using the KnownType Attribute to no avail. What am I missing? I have attached a zip file with the projects. You will need to add a reference to the service since some filetypes are not allowed to be uploaded.