If you study the block diagram, you see that only after all the samples (1000 in your case) have been collected, will the resultant array of data output.
To view each single sampling of data in realtime (or near realtime), you need to keep the samples value set to 1, and then perform this collection of single-sampling about 1000 times. Do this by putting the collection vi (HP34401A App. Example.vi), Error Query & Error Message VIs, and the Output Array in a For loop where the N is set to 1000 or wired to a control from the front panel.
Good luck with it, Doug