Check ur php.ini settings

How? open a notepad and type this

<?php

phpinfo();

?>

and save as phpinfo.php and upload it to your server. Go to yourdomain.com/phpinfo.php and check for the output_buffering setting. My guess is it's OFF.

how to turn it on?

open a notepad and type this

output_buffering = On

save it as php.ini and upload it to you server.

This should work.

Just my two cents..