NI OPC server

[DaveM]

I have package written and deployed to about a dozen machines. It communicates to a PLC through the NI OPC server.

My issue is that this package doesn't work on some machines I deploy it on ... cannot connect to the OPC Server.

I have stripped the app down to one indicator with its data socket field hard coded to a valid tag on the server - as simple as you can get. It works on all the machines that can talk to the OPC server and it doesn't connect on any of the other machines ... i.e. the DataSocket LED stays RED.

I cannot figure out what the difference is between these machines (or, alternatively, what is on the OPC Server which causes it to see these machines differently (talk to some and refuse others)).

I am the network admin here so I have looked at all the standard issues like firewalls and windows permissions.

Any ideas would be appreciated.

Dave

[asbo]

This is pretty basic, but since you didn't mention it specifically: are you using the exact same runtime version? Are they all using the same OS patches? Are they all even the same OS, for that matter? Do they all have the same resident processes? Logged in with the same user privileges?

[GoGators]

I have stripped the app down to one indicator with its data socket field hard coded to a valid tag on the server - as simple as you can get. It works on all the machines that can talk to the OPC server and it doesn't connect on any of the other machines ... i.e. the DataSocket LED stays RED.

Sounds like a DCOM settings problem. If you use Server Explorer or OPC Quick Client, can you connect to it? If not then I would definitely say DCOM setting. Look at the computers that work DCOM setting and try to emulate it on the others.

[Tim_S]

DCOM settings and using Quick Client have been mentioned.

I assume you're using LabVIEW 2009, however there is some strange behavior with the datasocket primatives with OPC with LabVIEW 8.x. The 2009 OPC client example uses the primatives, which is different than the 8.X version. You should use the legacy datasocket VIs if you're using 8.X.

Tim