Authcache error: Cannot modify header information - headers already sentv

Warning message

JQuery Cycle must be installed in order to run the slideshow. Please go to Status Report for instructions.

Primary tabs

You have to open authcache.helpers.inc and add if (headers_sent()) return; to the top of _authcache_shutdown_save_page().

Please refer to this post https://drupal.org/node/758380