OPC UA PubSub Configuration Error (PLCN0031): '...': The variable '...' was not found in the current configuration or it does not have a supported type.

In the configuration of the OPC UA PubSub communication, a variable is included in a data set which is not available in the project.
Possible reasons:

The port/variable has been deleted or renamed afterwards.
The data type of the port/variable has been modified afterwards. The PubSub communication supports elementary data types and one-dimensional arrays of an elementary type.
The 'Usage' of the port/variable has been changed. The PubSub communication supports OUT ports (but no IN ports) and resource-global variables (no locals or In/Out variables).

Remedy

Make sure that the ports/variables included in a data set actually exist with a correct name, usage and data type in the project.
You can:

refactor the affected port/variable accordingly,
or add the modified port/variable to the data set,
or remove the port/variable from the data set.

Example