[Plugin: WordPress Ping Optimizer] headers already sent error > cannot login admin anymore after

error :

PHP Warning: Cannot modify header information – headers already sent by (output started at /home/internetbi/domains/internet-business-revolution.com/public_html/wp-content/plugins/wordpress-ping-optimizer/cbnet-ping-optimizer.php:620) in /home/internetbi/domains/internet-business-revolution.com/public_html/wp-content/plugins/feedburner_feedsmith_plugin_2.3/FeedBurner_FeedSmith_Plugin.php on line 114

error:

home/internetbi/domains/internet-business-revolution.com/public_html/wp-content/plugins/wordpress-ping-optimizer/cbnet-ping-optimizer.php:620

http://wordpress.org/extend/plugins/wordpress-ping-optimizer/