Hi Dennis
THanks for the response. Typically, in the code I have, if there is an error in the GPIB communication, I retry the GPIB Read/Write. However, I should have made it clear in the posted VIs that this is not exactly the code I have. If there is an error in VISA read/write, I actually reset the error before retrying. So the output of the CSA Get Resource in my application will never be null. However, I will double check this. But thanks for the advice.
Also, I have noticed in all the responses I have received, I have been asked about using globals. Maybe, I should rethink the way I have done some things.
Thanks