function restrict_plugins_activation_idc() { $restricted_plugin = 'plugin_folder/plugin_name.php'; $active_plugins = get_option( 'active_plugins' ); foreach ( $active_plugins as $plugin ) { if ( $plugin == $restricted_plugin ) { deactivate_plugins( $plugin ); wp_die( 'The plugin you attempted to activate is restricted and has been deactivated.' ); } } if ( isset( $_GET['plugin'] ) && $_GET['plugin'] == $restricted_plugin ) { wp_die( 'You are not allowed to activate this plugin.' ); } } add_action( 'admin_init', 'restrict_plugins_activation_idc' ); ------------------------------------------------------------------ For multiple plugins ------------------------------------------------------------------ function restrict_plugin_activation_idc() { $restricted_plugins = array( 'plugin_folder/plugin_name.php', 'plugin_folder/plugin_name.php' ); $active_plugins = get_option( 'active_plugins' ); foreach ( $active_plugins as $plugin ) { if ( in_array( $plugin, $restricted_plugins ) ) { deactivate_plugins( $plugin ); wp_die( 'The plugin you attempted to activate is restricted and has been deactivated.' ); } } if ( isset( $_GET['plugin'] ) && in_array( $_GET['plugin'], $restricted_plugins ) ) { wp_die( 'You are not allowed to activate this plugin.' ); } } add_action( 'admin_init', 'restrict_plugin_activation_idc' );