This error is telling you that the outer-join syntax that you are using is not TRANSACT SQL. By default Reporter uses TRANSACT SQL to build queries. This is the *= syntax for the outer join. If the query contains the syntax "LEFT OUTER JOIN", this is ANSI SQL and Reporter does not recognize this without setting the DBMS value in the registry for the DbmsListForSql92OuterJoin setting. This setting is located under:
This setting takes a comma separated list of DBMS names. The DBMS name can be found in an ODBC trace. For example, SQL Server's DBMS name is Microsoft SQL Server.