Every LabVIEW project has its own FieldPoint configuration associated
with it. So in your case, you had an IAK configuration file with the
correct information you created from MAX, but the IAK file for your LabVIEW project was
empty. If you run a FieldPoint VI outside of a project context, then the IAK configuration saved from MAX will be used.
You should add the FieldPoint hardware to your project configuration - you can do this by importing your IAK configuration file you saved in MAX, into the LabVIEW project. Do this by right clicking on the project root and selecting "Import >> FieldPoint Configuration", and browsing for the IAK file you saved from MAX. Alternatively, you can right click on your project root and select "New >> Targets and Devices..." and manually add the hardware to your project, similar to what you already did in MAX.