Hi Nico,
The function call you indicate is a NI-DAQ call, what you need to do is install NI-DAQ support for CVI, This can be done using the Driver CD that ship with the Evaluation verion of the complete version of CVI. If you downloaded a evaluation you can also need to download the drivers that your appliction need. The driver CD's contain all our drivers, of which you probably only need NI-DAQ.
You can download our drivers from:
http://digital.ni.com/softlib.nsf/MainPage?ReadForm&node=132010_USMet vriendelijke groet / Kind regards,
Karsten
Applications Engineer
National Instruments