What causes Concept error "-4017 Link failed"?

Cause:
  The link cannot be created during text import & build of an FBD section.

Resolution:
    There is an unknown data type because there is a missing .DTY file.
    Verify that Concept has access to any needed .DTY files.  They should reside in either the C:\Concept\LIB folder or the local \GLB folder.