the Cannot modify header information - headers already sent error is caused by output on the page before the calling the header() or session_start() function.
this part of the error:
output started at /home/content/69/8169269/html/NewAniSnap/index.php:5
is saying that the problem is caused at line 5 of the index.php
lines 1- 5 of your file are:
<?php require_once( "webassist/security_assist/helper_php.php" ); ?>
the problem is caused by the blank line at line 4
see the following post for details on troubleshooting the headers already sent error: