I was working on a report which involved several tables and relationships between these tables.
I made sure that I’ve loaded and filled the table sources I tried launching my report but kept on getting the error “Unknown Database Connector Error”.
After a little bit of debugging what I suspected was true. You have to make sure that the tables or the tables’ links are executed in a correct order that doesn’t break the relations.
Basically it is best to load the father tables and then children tables.
To do that open the Database Expert which comes with Crystal Reports -> Links -> Order Links
It worked for me without checking the “Link ordering is enforced”.
Hope this helps 🙂