# Can't connect Plant Scada OPC UA server **URL:** \ **Category:** Ignition\ **Tags:** perspective, ignition81\ **Created:** [June 30, 2025, 1:01am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915 "2025-06-30T01:01:12Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![uy\_huynh](https://avatars.discourse-cdn.com/v4/letter/u/54ee81/32.png) [@uy\_huynh](https://forum.inductiveautomation.com/u/uy_huynh)\ **Post date:** [June 30, 2025, 1:01am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/1 "2025-06-30T01:01:12Z")
Hi guys, I'm trying to connect a Plant Scada ver 8.4 OPC UA server to ignition but having connection reset java.net.socketexception error. I've also checked the port of the opc server is open. Not sure if I did anything wrong. Any insights would be appreciated! ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/c/6/c6badd42991c04356f6f1e7befbfa9c85cacd1e7.png) ![u032y71f](https://us1.discourse-cdn.com/inductiveautomation/original/3X/0/d/0d8342f913134c50e00b5d6c7bc62c25b104b5f5.png) ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/c/9/c948a865135de60d6ba3938685598f28d6cb0e6f.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [June 30, 2025, 1:05am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/2 "2025-06-30T01:05:53Z")
Connection reset means the connection is being closed by the other side. Usually a firewall issue, sometimes it means the service isn’t actually running, sometimes other things. Nothing wrong on the Ignition config yet. You probably wouldn’t be able to connect e.g. UaExpert from the same server Ignition is on either. ---
**Author:** ![uy\_huynh](https://avatars.discourse-cdn.com/v4/letter/u/54ee81/32.png) [@uy\_huynh](https://forum.inductiveautomation.com/u/uy_huynh)\ **Post date:** [June 30, 2025, 1:11am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/3 "2025-06-30T01:11:56Z")
Thanks Kevin for quick response. I'll start to look at firewall stuff first. Do I need Kepware in my case? ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [June 30, 2025, 1:12am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/4 "2025-06-30T01:12:56Z")
You don’t need Kepware for anything you’ve shown or mentioned here. ---
**Author:** ![uy\_huynh](https://avatars.discourse-cdn.com/v4/letter/u/54ee81/32.png) [@uy\_huynh](https://forum.inductiveautomation.com/u/uy_huynh)\ **Post date:** [June 30, 2025, 1:20am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/5 "2025-06-30T01:20:19Z")
Thanks. I'm not the IT expert! Silly question, if you can Test-Netconnection to the opc port of target opc server, and it comes back with the TcpTestSucceeded:True as picture below, you would think it can somehow talk to target opc server over firewall? ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/c/9/c948a865135de60d6ba3938685598f28d6cb0e6f.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [June 30, 2025, 1:35am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/6 "2025-06-30T01:35:10Z")
Yeah, might not be firewall, might be the actual server itself closing the connection for some reason. Try UaExpert. I don’t expect that to work, but if it does, Wireshark might let you make a comparison and figure out why. ---
**Author:** ![uy\_huynh](https://avatars.discourse-cdn.com/v4/letter/u/54ee81/32.png) [@uy\_huynh](https://forum.inductiveautomation.com/u/uy_huynh)\ **Post date:** [June 30, 2025, 2:14am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/7 "2025-06-30T02:14:22Z")
![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/c/ac337fa1f24c0f3d3212eacaf06c5821421ad134.png) You are right. Can't use UAexpert to connect. Probably something is wrong on the other end. ---
**Author:** ![xolani.mzaca](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xolani.mzaca](https://forum.inductiveautomation.com/u/xolani.mzaca)\ **Post date:** [February 25, 2026, 1:55am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/8 "2026-02-25T01:55:52Z")
Hi, did you finally get a solution to this problem? Please share how you resolved it. ---
**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:** [February 25, 2026, 2:09am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/9 "2026-02-25T02:09:47Z")
Did you try the steps suggested by others in this thread? Did you try UA Expert? Everyone's problems may be different, so the solutions won't necessarily be the same. ---
**Author:** ![xolani.mzaca](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xolani.mzaca](https://forum.inductiveautomation.com/u/xolani.mzaca)\ **Post date:** [February 25, 2026, 2:41am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/10 "2026-02-25T02:41:50Z")
I haven’t tried any steps yet, but I’m looking at implementing the same setup and wanted to check what I should avoid and whether this is likely to become a recurring issue. ---
**Author:** ![uy\_huynh](https://avatars.discourse-cdn.com/v4/letter/u/54ee81/32.png) [@uy\_huynh](https://forum.inductiveautomation.com/u/uy_huynh)\ **Post date:** [February 25, 2026, 6:46am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/11 "2026-02-25T06:46:42Z")
It was working. Somehow I managed to make it not working today anymore 😂. But here are what I’ve done: - In configurator, turn off anonymous and turn on encrypted for opc ua server tab. You might see trouble restarting the conectivity service when hit configure button - Set up window account for citect security with full permission level - Use opc ua url with the window account to connect. - Ofc, you need to trust cert for both server and client. ---
**Author:** ![xolani.mzaca](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xolani.mzaca](https://forum.inductiveautomation.com/u/xolani.mzaca)\ **Post date:** [February 26, 2026, 12:45am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/12 "2026-02-26T00:45:44Z")
Thanks for this, that’s really helpful. It gives me a solid starting point for a similar set up I’ll be working on soon. ---
**Author:** ![uy\_huynh](https://avatars.discourse-cdn.com/v4/letter/u/54ee81/32.png) [@uy\_huynh](https://forum.inductiveautomation.com/u/uy_huynh)\ **Post date:** [March 3, 2026, 5:25am UTC](https://forum.inductiveautomation.com/t/cant-connect-plant-scada-opc-ua-server/107915/13 "2026-03-03T05:25:26Z")
Hi Xolani, Have you started?