Meaning: Failed to create the ruled surface geometry, it will not display. The Port selected as input is not of the correct type. It must be a PortEdge or PortVertex(in the future).
Recovery: Verify that all the inputs are properly identified and are not on the To Do List. They must be of the type curve, point or a port (edge or in the future vertex). If proper input has been provided and the problem still exists, report steps taken to your support group.