Hello, I have the same trouble. But even when I use your project xxx with the user and role, I got the same message when going to monitor mode. (Connection to OPC UA server not possible. (For more details please refer to the help.)) I am desperate. I do not know what to try next.

Hello Christopher, thanks for this link. The issue was as described in that link - the port 4840 was used by other process. I just changed it to 4841 and it works now.

I just posted on a different question but sounds like you have a similar issue and the OpcUa server is not enabled. Please check [image] Cant simulate offline B&R Software & Runtime Not sure where the help link leads but my guess would be that you need to enable the OpcUa system in the configuration. This help section explains the steps OpcUa server configuration or check out this page explaining the required setup for Ladder monitor mode

Thanks, Marcel, just want to add this link: No OPC UA connection to ARsim

Port conflict causing OPC UA failure

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marcel.voigt (Marcel Voigt) November 9, 2025, 9:35pm 2

I just posted on a different question but sounds like you have a similar issue and the OpcUa server is not enabled.
Please check

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Port conflict causing OPC UA failure

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