Trying to connect to a database using SQL Navigator returns the error message "ORA-01437: cannot have join with CONNECT BY."
WORKAROUND 1:
Upgrade to the latest version of SQL Navigator.
WORKAROUND 2:
Researching the error message online, it maybe related to an Oracle 10g parameter _old_connect_by_enabled being set to TRUE. This is an unsupported Oracle hidden Oracle parameter, by default it is off. Try turning it off by running the following (please try on a test database first, as it is unknown what it might do to the preformance of a production database.) You must be DBA to run the statement.
alter system set "_old_connect_by_enabled" = false;