求助一下，为什么代码一到虚拟空间就莫名奇妙错误

nevergiveup

A PHP Error was encountered
Severity: Warning

Message: Cannot modify header information - headers already sent by (output started at /htdocs/application/controllers/welcome.php:1)

Filename: libraries/Session.php

Line Number: 675


这个代码错误指向 <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
请大家不吝赐教啊！

nevergiveup

Utf-8 Bom 问题，炒了段代码运行了一下 OK了！