Why Do I Have A Warning Sign And Error Message On My OPC Variable?

Updated Feb 15, 2018

Reported In


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

Operating System

  • Windows

Issue Details

In my LabVIEW project my OPC variable has a yellow warning icon and when I right click and select "Explain Warning" I receive an Unsupported Item pop up message with one of the following messages:
The License for OPC I/O Server type is invalid.
LabVIEW currently cannot load the selected item. The required module, driver, or plug-in either is not installed or has an expired license. Ask the creator of the item or its project what software it requires. Contact NI for help identifying the software.


This means that you require the Datalogging and Supervisory Control Module that corresponds with the version of LabVIEW you are using. Installing and activating the module shall fix this issue. Ensure Datalogging and Supervisory Control Module is activated in NI License Manager and it shall appear under "Add-ons".


Not Helpful