Thanks for your interest.
I only get this error on apache on my development machine (Windows 98) - when I put the files on my website (Linux), they work fine.
It hasn't been a problem in the past, since I've been including commented out HTML to make up 350 characters!
But now I'm trying to redirect using the header() function - I believe this is an extreme case of absolutely NO characters and obviously I get the same error.
The following code works fine on my website, but on my local server, 500 Internal Server Error.
[FONT=courier new]
<?php
$Redirect = "redirect.php";
header("Location: http://".$SERVER['HTTP_HOST']
.dirname($SERVER['PHP_SELF'])
."/".$Redirect);
exit;
?>
[/FONT]