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Connecting OPC Client in Lookout 6.0 to another Lookout server OPC in the same network.

I rememeber that this question was answered long ago, but I cannot find it.


I have several computers running Lookout 6.0.2 SERVER with OPC client to a Delta Tau Motion Control each. The connection between Lookout and Delta Tau is OPC as a local service because the motion card is plugged on the motherboard in each computer. This is working just fine.


Now, I know that Lookout server is by itself a big OPC server, that does not need to be set up!


However, I have a computer dedicated to diagnostics which I would like to connect to the other PCs running Lookout via OPC as a remote service. All the computers are in the same local network level, no router, no gateway. I could say that all the computers are connected to the same ethernet switch.


I have been playing with the OPC Client of this new computer for diagnostics, I can see the processes with OPC from other computers, but I can not get a connection to any remote system variable. Even I can see the folders containing the objects of the other processes, but they can not be opened to get the objects.


Any one has done this before?

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Message 1 of 6

To connect remote OPC Server, follow this article to do the DCOM configuration.


Then, open the 'Local security settings' window. (Control Panel -> Administrative Tools -> Local Security Policy), select 'Security Settings -> Local Policies -> Security Options'. Make sure the value of policy 'Network access: Sharing and security model for local accounts' is 'Classic - local users authenticate as themselves'.

Ryan Shi
National Instruments
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Message 2 of 6

I did all that and I can now see the objects inside the folders in the OPC server side from the Client side. I can even click and drop the value of a pot from the Server onto the Client screen.


The thing is that all show ZEROES, not the actual value.


Any other suggestion?


Thanks in advance.


Rudy Lopez

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Message 3 of 6

What's your opc client software on the remote computer?


If you use OPClient object in lookout as the client on the remote computer to connect the lookout opc server, use the attached ini file to log the opc communication. Put the ini file to lookout folder, restart lookout. The opc communication through OPClient object will be logged to the file located in D:\. The file name is the object's name. Let me have a look at the log file.


You can also try the Server Explorer. If you don't find it in Start->All Programs->National Instruments, you can download it from


It is an opc client utility. Run the Server Explorer, expand the network and remote computer, right click on LookoutOPCServer, use the Wizard to create tags. Hope it will work.

Ryan Shi
National Instruments
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Message 4 of 6

The thing is that  I have done previuosly the whole thing in my office using my own desktop as the client, and a computer that is identical to the ones I have in the field, with the same Lookout application as in the field. I put the two computer through the same switch in my office and it did work.


In the field, I mean in our plants, there is a switch dedicated to these computers in production machines running the server. Connected to same switch I have what we call a service Computer that is the client. All these computers are in the same building and connected to the same switch.


In my office it works, in the fiel it looks like working but the variables in  the client side are equal to zero.



Best regards.


Rudy Lopez

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Message 5 of 6
So, the opc log file may help us to figure out what data the client exactly got from the server. If it got no repsonse or unexpected response, we can say the communication through the network has the problem.
Ryan Shi
National Instruments
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Message 6 of 6