[RESOLVED] session_start()??

[gc40]

How do I get rid of this error from display when I call session_start()??

Warning: session_start() [function.session-start]: 
Cannot send session cache limiter - headers already sent (output started at D:\My Documents\My Xampp\htdocs\ellen\header_top.php:4) 
in D:\My Documents\My Xampp\htdocs\ellen\header_top.php on line 5

[sneakyimp]

You need to call session_start before ANYTHING has been output to the browser. If you have any echo statements before your session_start call it's not going to work. Also, if you have an empty line or some spaces before your opening <? tag then that would also cause the problem.

Looks to me like line 4 outputs something.