Error message

I am being prevented from doing things like upload my logo for my new homepage on the bp-corporate theme, this is what I am getting and I have no clue what to do about it, can anyone help? :slight_smile:

Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, 'widget_wpAmember_init' was given in /home/batten/public_html/wp-includes/plugin.php on line 406

Warning: Cannot modify header information - headers already sent by (output started at /home/batten/public_html/wp-includes/plugin.php:406) in /home/batten/public_html/wp-includes/pluggable.php on line 876