Seems like there are some characters before the protection string in the fileUpload2.php.
Protection string must be the first line in the file, and no spaces/tabs/line breaks, or any other characters allowed before it.
So fileUpload2.php must start with <?php include("/usr/local/psa/home/vhosts/digitalsun.us/httpdocs/uploadScript/password_protect.php"); ?>
and than your code. If that does not help please email me your fileUpload2.php to look at this issue.
Also it should only request password once. When password is entered first time, script saves it in cookies and does not request password further.
Sample
password protection.