VISA IC 3.2 fails to detect NI GPIB

[doug80910]

After installing NI VISA 3.2 I am experiencing an intermittent state where
the NI VISA Interactive control cannot find the NI GPIB card. Sometimes, while in this
state, LabView 7.0 can access the gpib as well as Agilent's VISA assistant. The tulip
connection appears for appears to work for Agilent's VISA. Other times no program or
VISA control can access the gpib card. This problem started with NI VISA 3.1 which had
other undesirable behavior. I have not been able to reproduce the problem at will
and a system reboot is required to clear the condition. Running Windows 2000 SP4.
Wondering if anyone else has seen a similar problem.

[JohnM 64]

Hi Doug,

There are sometimes strange issues that can happen when using two different drivers for VISA at the same time. Certain actions by one driver can affect the behavior of the other. Have you attempted uninstalling Agilent VISA and seeing if this problem still occurs? I think this would be a good troubleshooting step, as we can then determine whether we need to look at how the Agilent and NI VISA's are interacting, or simply at NI-VISA itself.

John M
Applications Engineer

[doug80910]

I and my customers have been able to reproduce the problem fairly consistently by starting
with all instruments and the PC host powered down followed by powering up the PC and logging
in, etc. After the PC is stable and applications started, power up an Agilent scope(all I have
to test with) and Visa Interactive Control will frequently fail to find any interfaces.
Sometimes closing Microsoft applications such as Outlook and/or Explorer will fix the problem.
I have solved my immediate problems by going back to Visa 2.6.1.