Joom!Fish config error: Default language is inactive!

Please check configuration, try to use first active language

Warning: Cannot modify header information - headers already sent by (output started at D:\xampp\htdocs\joomla\plugins\system\jfrouter.php:301) in D:\xampp\htdocs\joomla\plugins\system\jfrouter.php on line 316

Warning: Cannot modify header information - headers already sent by (output started at D:\xampp\htdocs\joomla\plugins\system\jfrouter.php:301) in D:\xampp\htdocs\joomla\plugins\system\jfrouter.php on line 317

Warning: Cannot modify header information - headers already sent by (output started at D:\xampp\htdocs\joomla\plugins\system\jfrouter.php:301) in D:\xampp\htdocs\joomla\plugins\system\jfrouter.php on line 318