'derived-class member' hides inherited abstract member 'base-class member'
A base class method is hidden. Check the syntax of your declaration to see if it is correct.
The following sample generates CS0533:
namespace x { abstract public class a { abstract public void f(); } abstract public class b : a { new abstract public void f(); // CS0533 // try the following line instead // override public void f(){} public static void Main(){ } } }