오류가 나는곳의 주소를 알려주시면 더 빠르고 정확하게 답변 받을 수 있습니다.

오류 주소 : http://lgeivi.com/main.php

http://lgeivi.com/test.php

test에선 잘됩니다 main에 가면 에러납니다
이유가 뭘까요

Warning: Cannot modify header information - headers already sent by (output started at /home/hosting_users/lgivi/www/main.php:7) in /home/hosting_users/lgivi/www/lib/common.lib.php on line 109

Warning: Cannot modify header information - headers already sent by (output started at /home/hosting_users/lgivi/www/main.php:7) in /home/hosting_users/lgivi/www/lib/common.lib.php on line 109

Warning: Cannot modify header information - headers already sent by (output started at /home/hosting_users/lgivi/www/main.php:7) in /home/hosting_users/lgivi/www/lib/common.lib.php on line 109

이런 오류 메세지가 나와요 ㅜㅡ