I am receiving this error when trying to run a co-simulation.
NI LabVIEW Control Design and Simulation Module support for LabVIEW 2018 is missing.
Why exactly would I be having this problem. Is there a compatibility issue?
The NI LabVIEW Control Design and Simulation Module is not the same as the LabVIEW Multisim Co-Simulation Plug-in.
This error means that you do not have installed this module for LabVIEW 2018.
However, if what you are trying is to run a LabVIEW Multisim Co-Simulation, you'll need to work with LabVIEW 2015 or LabVIEW 2016.
As shown in the Multisim 14.1 installer, these are the only two LabVIEW versions that support the co-simulation plug-in.
NI LabVIEW Multisim 14.1 Co-simulation Plug-in support