This exception is thrown when you attempt to invoke a nonstatic method on a null object reference. (Note that in Beta1 of the .NET SDK, it was permissible to call a nonvirtual method against a null reference, so long as that method didn't access any of the fields in the type. In Beta2 and beyond, this "feature" has been closed and removed.)

public class TargetException : ApplicationException {
// Public Constructors
   public TargetException( );
   public TargetException(string message);
   public TargetException(string message, Exception inner);
// Protected Constructors
   protected TargetException(System.Runtime.Serialization.SerializationInfo info,
       System.Runtime.Serialization.StreamingContext context);
}

Hierarchy

System.Object System.Exception(System.Runtime.Serialization.ISerializable) System.ApplicationException TargetException