When configuring DAQ such as the M-series etc. as I configure the PFI connections I always read the "I" as a "1" e.g. PFI4 as connection 14.
Please change it from "PFI4" to "PFI 4" or "PFI_4" or anything better!
I know this is really a DAQ problem but LabVIEW could present the terminals better in the purple DAQ box
Al