The error is correct though I could see how the description starts ok and then veers off-track. It takes a little while for the cDAQ chassis and modules to be initialized and ready for use. If you are running your application at startup, it is likely that it is running before cDAQ is ready. It works when you run it manually because that takes longer. The fix is to have your code query if the devices are present before executing the rest of the application.
