This operation expects only one input. Check IJGeometryGeneration->SetParents (Structural Detailing)
Meaning: The software failed to create or update a collar part because the wrong number of inputs were given. This operation expects only one input. The collar part being created or modified. Because this is unexpected, it could be a memory problem or a database corruption.
Recovery: If this is a modify operation, try another re- compute. If this is a create operation, restart the command. Possibly need to reboot to free any memory. Run the Database Integrity report, which may provide further information. Verify that all inputs are good and are not on the To Do List. Make any necessary corrections. If problem still exists, report steps taken to your support group.