Go to this link http://vmetrix.home.comcast.net/~vmetrix/downloads
You can download the source code for a large application that uses GPIB-USB-HS with VB6.
If you have a problem with the download or other questions: firstname.lastname@example.org
I am facing similar problem, but almost sure it is OS related.
My system here is a Win 7 64bits, I downloaded the latest drivers and software from NI site. I am using a VB6 pro edition. In this system, the serial poll query is not working properly for any equipment. Sometimes after performing a serial poll, where the status byte indicates that the MAV bit is set, the following command is ibread to the instrument which returns an empty string or simply times out. If I do not perform the serial poll, the ibread command returns string as expected. I checked and enabled the bits with *SRE accordingly, even this command sometimes hungs when sent to the equipment. If I go to a Win XP 32 bits, the program runs properly.
Are you using the same GPIB devices on both systems? Have you also checked in Measurement & Automation Explorer to see if the GPIB controller's settings are identical between the 2 machines? Specifically make sure that the autopolling settings match on both systems.
I also ran across this tidbit of information in the GPIB driver help. If you are using a 64-bit application this could cause issues as well.
I wrote a VB6 program using NI USB GPIB card. The program runs OK in VB6 edidtor, but when I make an executable version of it, error : file not found: gpib-32.dll.
Are you running this executable on the same computer or on a different computer? On my computer, this dll is found in SysWOW64.