I have set up a OPC server using the python minimal server for the OPC UA on github. This is the message show when the correct address is entered.
“object reference not set to an instance”.
Please assist me on resolving this issue
Try to set an IP address rather than 0.0.0.0 as the server endpoint, such as 127.0.0.1. Next, copy and paste (or type) the server endpoint into the OPC Server field in Factory I/O. Press Return to connect. Please let me know if this works for you.