BuddyPress.org

Hello,

I have an problem with groups. It gives the error
Warning: sprintf() [function.sprintf]: Too few arguments in /home/public_html/wp-content/plugins/buddypress/bp-groups/bp-groups-loader.php on line 478.

When I am at the directory, everything is good, but when I go to the group page, it will give the error on the top of the page, above the header.
If i try to join a group, I get a white page with the error:
Warning: Cannot modify header information – headers already sent by (output started at /home/public_html/wp-content/plugins/buddypress/bp-groups/bp-groups-loader.php:478) in /home/public_html/wp-includes/pluggable.php on line 1121

I use BP 2.0.1 and WordPress 3.9.1. My theme is Cbox.
Can anybody help me?

With kindly regards,
Tim van Gompel
(Sorry about my English)