PME inquiry: why would the VIP not be logging any data for a particular data recorder?

Environment:
Power Monitoring Expert 7.2.x, 8.x, 9, 2020

Resolution:
One possible reason a user may see no data for a particular data recorder is because one or more of the devices linked to that data recorder's inputs are not communicating. Verify all linked devices are communicating. If all devices are communicating check the ION System Log for any errors.