web能正常显示登陆画面，并能进行密码核对
但登陆后（无论是sysop还是guest）都显示

Warning: Cannot add header information - headers already sent by (output started at /var/www/html/site.php:27) in /var/www/html/bbslogin.php on line 31

Warning: Cannot add header information - headers already sent by (output started at /var/www/html/site.php:27) in /var/www/html/bbslogin.php on line 32

Warning: Cannot add header information - headers already sent by (output started at /var/www/html/site.php:27) in /var/www/html/bbslogin.php on line 33

Warning: Cannot add header information - headers already sent by (output started at /var/www/html/site.php:27) in /var/www/html/bbslogin.php on line 34

Warning: Cannot add header information - headers already sent by (output started at /var/www/html/site.php:27) in /var/www/html/bbslogin.php on line 45

然后就什么也没了
问一下这是什么问题
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FROM 218.1.192.*