Why can't I connect to my DSC OPC server from a remote client PC?

[markwysong]

I have two PCs, both with LabVIEW 7 express and the DSC module. One PC is the host, running NI-DAQ 7.1 and is used for the OPC server. The application runs perfect on the host machine. However, on the client PC, when I try to connect to the OPC server on the client, it won't connect.

What's worse is that it DID connect for a day, then quit. I've tried setting the DCOM to allow the client to run the OPC server, but still no connection. I'm at a loss as to why it won't work.


I've set up the host machine's C drive as a shared drive on the network, and I can see and connect to it from the client, so I know it's on the network. Any ideas?!?


Thanks,


Mark

[Jochen]

Mark,

here is a link to a document in the NI knowledgbase. Please follow the steps there in order to connect both PCs via OPC:

http://digital.ni.com/public.nsf/websearch/5C8A90CD57B279F286256C2C006F1EB4?OpenDocument

On the other hand I'm wondering why you try to connect two PCs running LabVIEW DSC via OPC. Network performance is much better when you use the network tag feature of LV DSC. Configuration is also much easier as you only need a valid TCP/IP connection and no other Microsoft mechanisms. Please refer to chapter 3-6 in the Datalogging and Supervisory Control
Module Developer Manual for more information about network tags.

Regards,

Jochen Klier
Applications Engineering Group Leader
National Instruments Germany GmbH

[markwysong]

I am using the tag server of LV DSC. The tag server connects to the host pc using the OPC server from NI-DAQ.

Mark

[Jochen]

Mark,

in this case the link I gave you in my last response is still valid. Please adjust the access rights to the registry keys mentioned as described.

Regards,

Jochen

[markwysong]

I'll check into it today on the registry keys, Jochen. I'm fairly certain that I did this, as I remember the paths it describes. But, I'll check just to make sure. Thanks for the help.

Mark