The customer was trying to view an Ecad XFATF file in the Active Workspace viewer.
He was seeing a blank but thought he has everything configured directly.
Solution
What was needed was the following:
AWC_defaultViewerConfig.VIEWERCONFIG
PCBFATF.Awp02dViewer=XFatf
VMU_Datasets
PCBFATF
VMU_FileSearchOrder
XFatf
Review the entries carefully since in this case the customer left the lowercase d out from in between the 2 and V in the first entry. It is imperative to match exactly as written, any other way will not work.
Notes