Use external link in the add sub menu
Last argument of function add_submenu_page is the name of the function to call when display the content of the page. As described here: http://codex.wordpress.org/Function_Reference/add_submenu_page The right use is: add_submenu_page( ‘antify’, ‘Plugins’, ‘Plugins’, ‘manage_options’, ‘plugins’, ‘my_function’ ); function my_function(){ echo ‘hello’; } If you want a separate file you can do this add_submenu_page( ‘antify’, ‘Plugins’, ‘Plugins’, … Read more