Session_start (); error

Session_start (); error message: test. php file content & lt ;? Phpinclude ('site _ test. php ');? & Gt; site_test.php file content & lt ;? Phpsession_start (); header ('cont session_start (); error
Test. php file content
Include ('site _ test. php ');
?>

Site_test.php file content
Session_start ();
Header ('content-Type: text/html; charset = utf-8 ');
?>

When test. php is opened, the following error is reported, which is hard to understand after a long time. why?


Warning: session_start () [function. session-start]: Cannot send session cache limiter-headers already sent (output started at/home/cybertry/public_html/logs) in/home/cybertry/public_html/idearforyou.com/site_test.php on line 2

Warning: Cannot modify header information-headers already sent by (output started at/home/cybertry/public_html/logs) in/home/cybertry/public_html/idearforyou.com/site_test.php on line 3
------ Solution --------------------
Session_start (); no output in front
------ Solution --------------------
What is site_test.php encoding? if it is UTF-8 encoding, check that there is no bom header.