메인 화면 젤상단 부분에 저런 문구 에러가 발생합니다 도움좀 부탁드리겠습니다.

====== 오류 문구 입니다 =======

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

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

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====== 이렇게 나왔어요 =========

======== common.php =========
// 보안설정이나 프레임이 달라도 쿠키가 통하도록 설정
header('P3P: CP="ALL CURa ADMa DEVa TAIa OUR BUS IND PHY ONL UNI PUR FIN COM NAV INT DEM CNT STA POL HEA PRE LOC OTC"');
======== 8줄 내용입니다 =========

------ head.sub.php 줄 내용 -------------------
// 캐쉬의 내용을 가져옴. 완전한지는 검증되지 않음
header("Content-Type: text/html; charset=$g4[charset]");
$gmnow = gmdate("D, d M Y H:i:s") . " GMT";
header("Expires: 0"); // rfc2616 - Section 14.21
header("Last-Modified: " . $gmnow);
header("Cache-Control: no-store, no-cache, must-revalidate"); // HTTP/1.1
header("Cache-Control: pre-check=0, post-check=0, max-age=0"); // HTTP/1.1
header("Pragma: no-cache"); // HTTP/1.0

-----------------------------------------------

-------- index.php 최상단 내용----------
<?
include_once("./_common.php");
include_once("$g4[path]/lib/latest.lib.php");


$g4['title'] = "";
include_once("./_head.php");

?>
--------------------------------------------
고수 님들 조언 부탁드리겠습니다.