This is the last suggestion I have for you. Just before your header do an echo.
For example
[php]
echo “Redirect”;
header(“Location: …/pages/login.php”);
[/php]
When you see the error, right click > view source. If you see anything before the word “Redirect” (a space, blank line, anything) then your header will not work.
Otherwise, you will have to post all your code. If you don’t want to post it here, feel free to send it to me in a private message.
Good luck