This error can occur in the following cases:
- The input network dataset does not support turns.
- There are no turn feature classes defined for the network dataset.
Do one of the following:
- If the ability to model turns was not been specified during network dataset creation, delete the existing network dataset and re-create it with the ability to model turns.
- If no turn feature classes were defined for the network dataset, add existing or newly created turn feature classes as turn sources for the network dataset and rebuild the network.