I'm not exactly sure what your problem is, but I'd like to point out that you are using a fairly old version of NI-DAQmx Base. Also, you mentioned you are using Windows XP, and from the looks of your program name, you are using a USB data acquisition device. If this is true, I strongly recommend using NI-DAQmx (instead of NI-DAQmx Base). You can download the most recent version of NI-DAQmx here.