Это есть оффтопик, но я отвечу : RTFM,RTFM,RTFM.

Nexus 07.10.2002 15:35

====================== PHP Manual =========================
function header()
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.....
Remember that header() must be called before any actual output is sent, either by normal HTML tags, blank lines in a file, or from PHP.
.....
Note:
In PHP 4, you can use output buffering to get around this problem, with the overhead of all of your output to the browser being buffered in the server until you send it. You can do this by calling ob_start() and ob_end_flush() in your script, or setting the output_buffering configuration directive on in your php.ini or server configuration files.

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Или у тебя проблемы с english ?

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