Changed Logon Service now OPC server not connecting

So to make it simple I had to change the Logon Service for Ignition which went in just fine. Everything is working as normal except for the information coming out of Matrikon OPC server. I assumed I wouldn't need to change anything on that end since it's Ignition is just pulling the tag directly from the IP. Basically I have the tag set as a OPC tag with the opc server as a view and that I just have it pointed directly to the IP address. 192.xxx.xxx.xxx\TcPLC.tcZ[01].Com.HMI_Deep_TC

Any ideas?

You seem to be mixing up your OPC connection URL that goes into a named connection in the gateway with the tag properties for OPC Server and OPC Item Path.

Please show more of your configuration.

The thing is nothing has changed on the tag except for the logon as a service username

I don't understand. That isn't a tag property. Show more of your configuration.

Ok sorry I think I found the issue the View in the OPC Connections has faulted. Would that be the reason? Would I need to change a setting in there to get it to work?


Almost certainly not there, but on the Matrikon side. It seems the Matrikon OPC DA connection was relying on the system privileges that the default service user has for local resources. You will probably have to figure out from Matrikon how to allow connections from the user you changed to.

If possible. (I don't know enough about Matrikon to say--OPC DA is a nightmare.)

You might want IA support to look over your shoulder.

Just wanted to add that I was looking at the OP Connection and it has this error:

com.jniwrapper.win32.com.ComException: COM object method returns error code: 0x80070005; E_ACCESSDENIED (Access is denied.)
	at com.jniwrapper.win32.com.ComException.checkResult(SourceFile:172)
	at com.jniwrapper.win32.com.ComFunctions.coCreateInstanceEx(SourceFile:230)
	at com.inductiveautomation.opccom.COMServerImpl$ConnectServerJob.internalRun(COMServerImpl.java:715)
	at com.inductiveautomation.opccom.wrapper.OleJob.run(OleJob.java:48)
	at com.jniwrapper.win32.MessageLoopThread$ThreadSynchronizedAction.run(MessageLoopThread.java:620)
	at com.jniwrapper.win32.MessageLoopThread$LoopThread.run(MessageLoopThread.java:562)

8.1.35 (b2023120517)
Azul Systems, Inc. 17.0.8

Would that be a firewall or something?

That perfectly fits what I just speculated at as the cause. It worked until you changed the user that Ignition runs as. So, not a firewall. You have to tell Matrikon to allow this new Windows user to connect. (I don't know how to do that.)

I don't know if it's even a Matrikon issue as much as it is probably a Windows DCOM issue. DCOM and OPC-DA is a dumpster fire and I try to stay away from it as much as possible. I would read the Matrikon documents on setting up DCOM properly on Windows both on the server and client sides to make sure they talk properly. If they're on a domain it helps also.

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