C# TCPIPsocketsession

[Psquared]

So, I'm connecting to another PC over ethernet.  On my end I am using Visual Studio 2022 in C#; on the other end it is LabView.  The guy on the other end made an update to the software and released a new revision, and since then my PC can no longer open a VISA session.  This is true even if trying to go through NI MAX, so I am confident the issue is not in code on my side.  The guy didn't change anything about the code for the remote connection and I in fact looked at it - it's about as simple as can be.  I am able to ping in both directions; it is only the VISA session that will not open.

Can anybody provide some insight on how a LabView update of any sort could cause code that was not modified at either end to stop working?  Version, drivers, etc. anything at all I'm not thinking of?  I'm spinning my wheels here.

[rolfk]

From the information you provide it is not really possible to make any sensible guess. Something changed but what?

A few thoughts:

- Why do you use VISA to communicate TCP/IP?

  Yes it can be done but unless you want to support communication with a device that also supports GPIB, or RS-232 interface, it has no advantage whatsoever (well except maybe that you are more familiar with VISA than with native TCP sockets in C#)

- Have you tried to have your colleague create a minimalist app that does the LabVIEW side of your communication (and do a similar thing for your side)?

  That not only exercises the seemingly trivial LabVIEW code that may in fact do some hidden things that are not immediately obvious, as well as would give you an option to actually upload something here for other people to look at. Without a simple example of both sides of what you are actually trying to do, we can try to consult our crystal balls for all kinds of occult wisdom but chances that anything useful will come from that are pretty much nihil. Most likely though, going this path will show you that it suddenly starts to work and then you can try to figure out what change caused it!