NotSupportedException is thrown when it is never possible for the object to perform the requested operation. A typical scenario is when a base class declares a method that derived classes are required to implement, and the method is invoked on the base class. When a method throws NotSupportedException this usually indicates that the derived classes must provide an implementation of the method, and callers must invoke the method on the derived class.

For scenarios where it is sometimes possible for the object to perform the requested operation, and the object state determines whether the operation can be performed, see InvalidOperationException .