My theme doesn't work properly with the Directory Plugin.

All page links give the following error, can you help?

Warning: Cannot modify header information - headers already sent by (output started at /home/content/14/11333014/html/askabankruptcylawyer/wp-content/themes/business-feature/header.php:2) in /home/content/14/11333014/html/askabankruptcylawyer/wp-includes/pluggable.php on line 899