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Is it important to close a VISA session?



My program sends several commands over GPIB using the write to VISA VI. It's built on what someone before me started, and he never used the VISA close function. I saw that the close function was under "advanced", and since the commands got through I though it wasn't needed. It wasn't until I started using TestStand that opens this LabVIEW VI several times during a test to send commands that I started getting errors about ActiveX.


For a while I have been blaming it on some DLLs that some other VIs use, but I'm starting to think it might be that I'm opening and closing this VI several times and never closing the session.


I have added the close function, but the problem is that the error occurs quite randomly. Sometimes several times in a row and other times a day or two might go by, so I can't really know if I have fixed the problem until I know that I haven'tSmiley Frustrated


So I just wanted to ask if anyone has had similar problems or know that it's important to close VISA sessions.


Thanks for having a look

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Sorry, this was realy ment for the LabVIEW forum

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