채팅중 오류...

채팅중에 50번 정도의 채팅글이 올라가면 아래와 같이 오류가 뜹니다.

어떻게 해결해야하나요?

고수님들의 시원한 답변 기다리겠습니다.

Warning: main(/head.sub.php) [function.main]: failed to open stream: No such file or directory in /home/hosting_users/masia85/www/bbs/chat.php on line 3

Warning: main() [function.include]: Failed opening '/head.sub.php' for inclusion (include_path='.:/usr/local/lib/php') in /home/hosting_users/masia85/www/bbs/chat.php on line 3

Warning: main(/tail.sub.php) [function.main]: failed to open stream: No such file or directory in /home/hosting_users/masia85/www/bbs/chat.php on line 175

Warning: main() [function.include]: Failed opening '/tail.sub.php' for inclusion (include_path='.:/usr/local/lib/php') in /home/hosting_users/masia85/www/bbs/chat.php on line 175