Compiler Warning C4687
'class': a sealed abstract class cannot implement an interface 'interface'
A sealed, abstract type is typically only useful to hold static member functions.
For more information, see abstract (Visual C++)and sealed.
C4687 is issued as an error by default. You can suppress C4687 with the warning pragma. If you are certain that you want to implement an interface in a sealed, abstract type, you can suppress C4687.