Not sure if you ever found a solution to this but I found this:
(here)
Open wp-config file and delete the inserted code at top of page which will look like this:
//Added by WP-Cache Manager
define(‘WP_CACHE’, true); //Added by WP-Cache Manager
define( ‘WPCACHEHOME’, ‘/home/XXXXXXXXX/public_html/XXX/wp-content/plugins/wp-super-cache/’ ); //Added by WP-Cache Manager
define(‘COOKIE_DOMAIN’, ‘XXXXXXXXXXXXXXX’); // Added by W3 Total Cache
It worked for me!!