CodeIgniter加载session类提示异常如何解决

CodeIgniter加载session类 提示错误 怎么解决
A PHP Error was encountered

Severity: Warning

Message: Cannot modify header information - headers already sent by (output started at F:\APMServ5.2.6\www\htdocs\application\config\config.php:1)

Filename: libraries/Session.php

Line Number: 672



我的config.php的一部分代码：

PHP code

求高手解答

------解决方案--------------------
config.php 首行是空行？