Hi...I am a novice when it comes to php - just enough knowledge to be dangerous

I have recently downloaded your file uploader program, and it works great on it's own - see
http://www.netnaimo.com/file-upload.php. It does as it should, it uploads the file and it redirects to the thank you page.
The problem begins when I try to use an "include statement. On this page:
http://www.netnaimo.com/uploader.php I have used an include statement calling the file that I know works. here is how I added the include:
Code:
<?php include("file-upload.php");?>
Now, when I try the uploader as it appears in the include, it still uploads the file, but I get this error:
Warning: Cannot modify header information - headers already sent by (output started at /home/cd2845/public_html/uploader.php:10) in /home/cd2845/public_html/file-upload.php on line 224Line 224 is:
header('Location: ' . SUCCESS_URL);
I have added a success url in the top of the page as:
define('DESTINATION_FOLDER','/home/cd2845/public_html/uploads/');. Thanks for any help Smiley
Abe