Bad_NodeIdUnknown: The node id refers to a node that does not exist in the server address space

Good morning Team,

I am getting this error on a tag with a connection to Ignition OPC UA Server.

Any idea on where I should look?


what opc UA server are you using ?


This is the server telling you it doesn’t recognize the OPC Item Path.

From the syntax it looks like a maybe a Logix device of some kind… so maybe it’s not connected, hasn’t browsed, or that tag simply doesn’t exist in the PLC program.

Thanks Kevin, that it what I thought. I need to verify what it is actually in the PLC.

hi Kevin
I wonder if using Kepware Operating Mode/Simulated to YES will suppress tags configuration errors ?

I don't know, you'd have to ask Kepware support probably.

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thanks for reply

Hi Kevin.

I have the same issue as ahawes. But I can't find the solution. I have checked the path and it looks OK. How can I find where is the problem?

In IgnitionEdge the device is connected

Thanks for feedback.
Best regards

Morning Joze,

I figured mine out by going to the PLC and looking at all the parameters. When I first copied over all my tags over from a previous project the paths were slightly different. I am not going back through and checking the PLC parameters and making corrections as needed.


We are almost at the end of the workday on this side of Atlantic. :slight_smile:

I also copied from a non RaspberyPi device to RaspberryPi device. Siemens side stayed exactly the same. Where did you find the change? In Ignition Designer or IgnitionEdge or PLC?


I found the difference in the PLC.

For example:

So, on the photoeyes had a PEType of “Jam” but the tags in the PLC were “Exit” which caused this error.

Changing that to the correct tag corrected the issue. You can tell if the path is incorrect by looking at the Ignition tags. If the tags for the photoeye that you are looking at say “Error_Configuration” then the PLC tag path is incorrect. We went in a verified PEType for that error should have said Exit_PE and not Jam.



Thanks for hint. I am afraid that my issue is in license. On Opto22 PLC I am running with bought license. On test environment (RaspberryPi) I am running with trial version of Ignition. This is the only difference I could find.

@ahawes Your hint was absolutely correct. The tag name must be 100% same as in (in my case) Siemens TIA portal. Otherwise it shall not work. On attached image I displayed same tag but named correct (humidity) and incorrect (NewTag)


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The tag name doesn't matter, only the OPC Item Path. If you look close at your screen shot, you can see a difference in the device names.. underscore versus hyphen.

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I got the connection with Kepware and Ignition.
yesterday I got connection, I was able to read tags in Ignition, but today after I reinitialize I am getting error in Tag Browser.



Can anyone please give the solution for above error

You haven't provide enough information. Get the Details, then copy, then paste here using the "Preformatted text" styling (button </> in the comment editor).

But "NodeIdUnknown" is just something handed off from the OPC server. (Are you using Kepware's trial mode?)

Yes I am using Trial version.

Yes I am using Trial version. can you please tell what are restrictions when we are using trial version.
can you please explain what is this notification.

  Error           ThingWorx Native Interface           Connection to ThingWorx failed. | Platform = localhost:443/Thingworx/WS, error = could not initialize a secure socket connection.