When you test your digital I/O in the NI-DAQ Configuration Utility Test Panels, do you get the error? What LabVIEW examples do you run that give you the error? Those examples are in the LabVIEW >> Examples >> Daq >> digital directory. Try physically removing the card and installing the card fresh. Make sure that you have followed the steps to install according to the DAQ Support pages at:
Then, try the Test Panels and the examples.