How to change value in mysql max_allowed_packet?

You have two values of mysql max_allowed_packet :

  one on the client side : [mysql] section, [mysqldump], [client] and more.

one on the server side : [mysqld] section.

The value of max_allowed_packet you see with the command show variables like 'max_allowed_packet'; is the one on the server side.
In order to increase this value, you must increase both sides : in your server configuration file ([mysqld] section in your my.ini file) and in your client configuration file (whether your [client] or [mysql] section in your my.ini file).
This setting can be changed on the server side without restarting the server if you have the SUPER privilege with this command : mysql> SET GLOBAL max_allowed_packet = numeric;.

Don't forget to change the 'numeric' value by a numeric value. Don't forget to change your configuration file too otherwise this value will be reset at reboot.