SharePoint 2010 Search File Type – Include or Exclude?
This is an old topic, but definitely worth mentioning. The “File Types” page of search service application has very different meaning for FAST Search Connector and FAST Search Query (or SharePoint Enterprise Search).
In FAST Search Connector, you add the file types that you do not want to be included in the index.
In FAST Search Query (or SharePoint Enterprise Search) , you add the files types that you do want to include in the index.