utf-8 소스수정 애러문의요

utf-8 로 그누보드를 설치했는데요
알ftp에서 수정만하면 애러가 뜹니다.

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Warning: Cannot modify header information - headers already sent by (output started at /home/hosting_users/hyeza521/www/index.php:1) in /home/hosting_users/hyeza521/www/head.sub.php on line 32

Warning: Cannot modify header information - headers already sent by (output started at /home/hosting_users/hyeza521/www/index.php:1) in /home/hosting_users/hyeza521/www/head.sub.php on line 34

Warning: Cannot modify header information - headers already sent by (output started at /home/hosting_users/hyeza521/www/index.php:1) in /home/hosting_users/hyeza521/www/head.sub.php on line 35

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이런식으로요..

머 저장방식때문에 그런지 띄어쓰기를 수정해봐도 이러네요
어떻게 수정작업을 해야하나요?