To check that you have the basic setup correct, you might want to follow the online demo that shows how to use Instrument Control Toolbox to connect to an instrument using a VXIPlug&Play driver.
I was unable to find the VXIPnP driver for the instrument you listed but you can refer to the help installed along with the VXIPlug&Play driver to learn more about which function to call with what parameters.
If that does work for you, you can also try using a GPIB object and communicate using the instrument's SCPI commands. Here's an example that shows how to create and communicate using GPIB object. The programming manual for the instrument that lists all the SCPI commands can be found here.
Hope this helps,
-Ankit