All the error messages that the connector generates are stored in a message file named JDBCConnector.txt or JDBCConnector_II_TT.txt (where ll specifies a language, and TT specifies a country or territory). Each error has an error number followed by the error message. For example:
20017 Connector Infrastructure version does not match.
20018 Connection from {1} to the Application is lost! Please enter 'q' to stop the connector, then restart it after the problem is fixed.
20019 Error: ev_id is NULL in pollForEvent().