Error 1556 When Creating New Data Value References in LabVIEW 2023 Q3

Issue Details

• I upgraded a project that uses the New Data Value Reference Function and In Place Element Structure to modify data to LabVIEW 2023 Q3 from a previous version. When I run the application in LabVIEW 2023 Q3 I get error.
• After upgrading to LabVIEW 2023 Q3, LabVIEW Modbus VIs are returning the error 1556:

Solution

This is a known issue when upgrading to LabVIEW 2023 Q3. There were changes in the behavior of DVRs from one version to another. There was no code version change, so VIs coming from earlier versions are not forced to compile on load, and their generated code will have the old behavior. A mix of old and new VIs may cause this unexpected behavior. This issue can also occur when using Modbus VIs since they use DVRs internally.

In order to workaround the issue you should recompile the LabVIEW code of the VIs causing the issue. To do this you need to narrow the source of the behavior and once you have identified the VIs throwing the error, you can recompile them by following one of these methods:

• Mass compile the LabVIEW VIs. 
• Find occurrences of the Data Value Reference Functions in your code and Ctrl-Click the run arrow of the VI causing the issue to force the compilation.