While creating a new Database Connection,there are 3 fields i.e. Agent URL,Username and Password.I believe Agent URL is the PerfectForms Agent and Username and Password are the same as given in SQL Database.
The Agent URL is correct, but the username and password are not. these you set in the configuration of the agent in the config.xml see here: perfectforms.com/Documentation/manual/html/admin_log_in_parameters.htm
the SQL user credentials are defined when you set up the datasource to that specific database: perfectforms.com/Documentation/manual/html/admin_datasources.htm
have a look at all the information on the use, security, troubleshooting etc in the connection agent section in the user guide: /Documentation/manual/html/lookup_agent.htm