Description
The Stops feature class in the target feature dataset must follow the format defined by the ArcGIS Network Analyst extension public transit data model.
Solution
Ensure that the Stops feature class in the target feature dataset follows the format defined by the ArcGIS Network Analyst extension public transit data model. You can correct the problem manually, or you can create a valid Stops feature class, along with other required data model tables, using the GTFS To Network Dataset Transit Sources tool.