The MySQL Server Instance Configuration Wizard is normally started as part of the installation process. You should only need to run the MySQL Server Instance Configuration Wizard again when you need to change the configuration parameters of your server.
If you chose not to open a port prior to installing MySQL on Windows Vista, you can choose to use the MySQL Server Configuration Wizard after installation. However, you must open a port in the Windows Firewall. To do this see the instructions given in Section 1.3.1, “Downloading and Starting the MySQL Installation Wizard”. Rather than opening a port, you also have the option of adding MySQL as a program that bypasses the Windows Firewall. One or the other option is sufficient — you need not do both. Additionally, when running the MySQL Server Configuration Wizard on Windows Vista ensure that you are logged in as a user with administrative rights.

You can launch the MySQL Configuration Wizard by clicking the MySQL Server Instance Config Wizard entry in the MySQL section of the Windows Start menu.
          Alternatively, you can navigate to the
          bin directory of your MySQL installation
          and launch the MySQLInstanceConfig.exe
          file directly.
        
          The MySQL Server Instance Configuration Wizard places the
          my.ini file in the installation directory
          for the MySQL server. This helps associate configuration files
          with particular server instances.
        
          To ensure that the MySQL server knows where to look for the
          my.ini file, an argument similar to this
          is passed to the MySQL server as part of the service
          installation:
        
--defaults-file="C:\Program Files\MySQL\MySQL Server 5.4\my.ini"
          Here, C:\Program Files\MySQL\MySQL Server
          5.4 is replaced with the
          installation path to the MySQL Server. The
          --defaults-file option
          instructs the MySQL server to read the specified file for
          configuration options when it starts.
        
          Apart from making changes to the my.ini
          file by running the MySQL Server Instance Configuration Wizard
          again, you can modify it by opening it with a text editor and
          making any necessary changes. You can also modify the server
          configuration with the
          http://www.mysql.com/products/administrator/ utility. For more
          information about server configuration, see
          Server Command Options.
        
          MySQL clients and utilities such as the
          mysql and mysqldump
          command-line clients are not able to locate the
          my.ini file located in the server
          installation directory. To configure the client and utility
          applications, create a new my.ini file in
          the Windows installation directory (for example,
          C:\WINDOWS).
        
          Under Windows Server 2003, Windows Server 2000, Windows XP,
          and Windows Vista MySQL Server Instance Configuration Wizard
          will configure MySQL to work as a Windows service. To start
          and stop MySQL you use the Services
          application that is supplied as part of the Windows
          Administrator Tools.
        

