Session (maybe cookies)

Hi all, I tried to start a session by this code: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <title>Untitled Document</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> </head> <body> <?php session_start(); echo(session_id()); ?> </body> </html> When I execute it I got the following error: Warning: session_start(): Cannot send session cookie - headers already sent by (output started at e:\rolf\sites\thinkquest\sessiontest.php:9) in e:\rolf\sites\thinkquest\sessiontest.php on line 9 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at e:\rolf\sites\thinkquest\sessiontest.php:9) in e:\rolf\sites\thinkquest\sessiontest.php on line 9 e183565b226d52b334b792e4b367221c These are the headers which my browser sended: GET http://localhost/sessiontest.php HTTP/1.0 Accept: */* Accept-Language: ie-ee,nl;q=0.7,is;q=0.3 User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0) Host: localhost Proxy-Connection: Keep-Alive And these are the headers which Apache returned: HTTP/1.1 200 OK Date: Tue, 03 Feb 2004 18:38:40 GMT Server: Apache/1.3.28 (Win32) PHP/4.3.3 X-Powered-By: PHP/4.3.3 Connection: close Content-Type: text/html Does anybody know why these errors occurs?? Waiting for answer, Rolf van de Krol