Revit does not support Undefined connectors. The following have been replaced by the default connector: [Connector Element]

public static FailureDefinitionId UndefinedConnector { get; }

Public Shared ReadOnly Property UndefinedConnector As FailureDefinitionId
	Get

public:
static property FailureDefinitionId^ UndefinedConnector {
	FailureDefinitionId^ get ();
}