andy – same errors as those reported above by other users. Couldn’t log in to admin area (‘Warning: Cannot modify header information – headers already sent by (output started at /home2/hamlin2/public_html/wp-content/plugins/church-admin/index.php:1)…’ When trying to log in to Admin area, was getting the ‘cookies’ error in addition to the above. I ended going back to release 0.565 before the problem went away. I can now log back in successfully.
Don’t worry – all fixed. Don’t install the latest version – not compatible with 3.8.1. Ended up manually downgrading to an earlier version to fix the problem.