Can't access dashboard

I can’t access my dashboard. I try to login and get this:
Warning: Cannot modify header information – headers already sent by (output started at /home/content/09/8264909/html/wp-content/plugins/wp-easy-gallery/wp-easy-gallery.php:191) in /home/content/09/8264909/html/wp-includes/pluggable.php on line
I have tried many times on different browsers and I can’t get past it. I searched the help and can’t get any help. What do I do. Please help.
kpcartography.com