# Changed Logon Service now OPC server not connecting **URL:** \ **Category:** Ignition\ **Tags:** ignition81, perspective\ **Created:** [May 29, 2024, 3:23pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079 "2024-05-29T15:23:54Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![scadafan](https://avatars.discourse-cdn.com/v4/letter/s/90db22/32.png) [@scadafan](https://forum.inductiveautomation.com/u/scadafan)\ **Post date:** [May 29, 2024, 3:23pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/1 "2024-05-29T15:23:54Z")
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? ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [May 29, 2024, 3:29pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/2 "2024-05-29T15:29:14Z")
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. ---
**Author:** ![scadafan](https://avatars.discourse-cdn.com/v4/letter/s/90db22/32.png) [@scadafan](https://forum.inductiveautomation.com/u/scadafan)\ **Post date:** [May 29, 2024, 3:30pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/3 "2024-05-29T15:30:01Z")
The thing is nothing has changed on the tag except for the logon as a service username ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [May 29, 2024, 3:31pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/4 "2024-05-29T15:31:16Z")
I don't understand. That isn't a tag property. Show more of your configuration. ---
**Author:** ![scadafan](https://avatars.discourse-cdn.com/v4/letter/s/90db22/32.png) [@scadafan](https://forum.inductiveautomation.com/u/scadafan)\ **Post date:** [May 29, 2024, 3:37pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/5 "2024-05-29T15:37:32Z")
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? ![OPCConnect1](https://us1.discourse-cdn.com/inductiveautomation/original/3X/5/f/5f80a52c66761ae9237eb527dc374ac69623679c.png) ![OPCConnect2](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/e/2eae87b811e877a28014c459d63518b13ec82559.png) ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [May 29, 2024, 3:40pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/6 "2024-05-29T15:40:35Z")
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. ---
**Author:** ![scadafan](https://avatars.discourse-cdn.com/v4/letter/s/90db22/32.png) [@scadafan](https://forum.inductiveautomation.com/u/scadafan)\ **Post date:** [May 29, 2024, 4:52pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/7 "2024-05-29T16:52:21Z")
Just wanted to add that I was looking at the OP Connection and it has this error: ```python 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? ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [May 29, 2024, 4:54pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/8 "2024-05-29T16:54:12Z")
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.) ---
**Author:** ![michael.flagler](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/michael.flagler/32/26272_2.png) [@michael.flagler](https://forum.inductiveautomation.com/u/michael.flagler)\ **Post date:** [May 29, 2024, 5:26pm UTC](https://forum.inductiveautomation.com/t/changed-logon-service-now-opc-server-not-connecting/91079/9 "2024-05-29T17:26:31Z")
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. > **[DCOM Configuration for OPC](https://www.matrikonopc.com/dcom-configuration-opc.aspx)** > > FAQs and Common DCOM problems: Because DCOM security is such a common concern it can cause communication problems for implementers of OPC systems, as it restricts the use of OPC technology to Windows operating systems. A certain amount of...