WordPress Navigation
You should hook it like this : function customwidget_init() { $args = array( ‘name’ => __( ‘Main Navigation’, ‘theme_text_domain’ ), ‘id’ => ‘sidebar-navigation’, ‘description’ => ‘Main Navigation Container’, ‘class’ => ”, ‘before_widget’ => ‘<div>’, ‘after_widget’ => ‘</div>’, ‘before_title’ => ‘<h2 class=”widgettitle”>’, ‘after_title’ => ‘</h2>’ ); register_sidebar( $args ); } add_action( ‘widgets_init’, ‘customwidget_init’); see Codex description