Solution
When a custom device is added to the system definition file, the initialization VI is called. This VI is dynamically loaded by NI VeriStand. If there is an inconsistency between the custom device XML and the custom device project, NI VeriStand will report these sort of errors.
The VeriStand custom device LabVIEW project has all the required targets added in it, along with build specifications for each target individually. If there a mismatch between the built files actually present in the custom device directory and the information present in the custom device XML file, NI VeriStand will report errors.
To resolve this, open the custom device XML in any notepad editing software and remove the targets from the XML for which you will not be compiling the build specifications via the LabVIEW project, as shown:
NOTE : Only one target is highlighted in the snapshot for demonstration purposes. You must remove/comment out the target(s) as per your requirements of the compiled custom device.