Shared Variables Don't Update on Client Side in NI-OPC Servers

Updated Jul 25, 2023

Reported In


  • OPC Servers
  • LabVIEW Datalogging and Supervisory Control Module
  • LabVIEW

Operating System

  • Windows

Issue Details

I had a working NI-OPC application that was working fine, but is no longer functioning. I have not made any changes to the code. The OPC Quick Client on the server side shows the correct variable values, but when I read the same variables on the client side in the NI Distributed System Manager, the variable values are either all zero or do not show up at all. How can I troubleshoot this issue?


This issue has been seen with a recent Windows 10 update (KB4056892) that affected the necessary DCOM settings to connect a server and client PC using NI-OPC Servers. This issue was resolved in Windows 10 update KB4058258. Make sure that you have the latest Windows updates installed on your machine.

If the problem persists, there are a few troubleshooting steps to try: