SYMPTOM:
After creating a new project, there are no tables in the warehouse catalog: This specific example is from an Oracle Data Warehouse.
Even after making sure that the customer has connected to the correct database instance with the correct database connection type and correct ODBC connection, there are still no tables in the warehouse catalog.

"No Available tables were found in the warehouse catalog. This can happen due to three possible causes:
a) All tables are already part of the project.
b) An incorrect custom SQL statement is being used, or
c) The warehouse connection is not defined correctly.
Do you want to modify the Warehouse Catalog Browser options? Please re-run the warehouse Catalog Browser after you make your changes."
The tables were not already part of the project and the warehouse connection was defined correctly, so the issue was with an incorrect custom SQL statement.
CAUSE:
An incorrect custom SQL statement is being used.
Click on the project->Schema->Warehouse Catalog
Tools->Options->Catalog->Read Settings
Click "Settings"
Customer clicked "use default" but did not change the "#LOGIN_NAME#".

ACTION:
Make sure you have the correct "#LOGIN_NAME#".
Even a "#LOGIN_NAME#" with read only settings will not bring back any tables.
Please contact your Database Administrator for which "#LOGIN_NAME#" to put in.