BuddyPress

The only links that work now are Home and Blog. Members, Forums and Blogs go back to the Home page. Groups gives the following error:

Fatal error: Call to undefined function bp_group_pagination_count() in…

Any help would be appreciated.

http://buddypress.org/community/groups/how-to-and-troubleshooting/forum/topic/when-asking-for-support/

When you upgraded WPMU to WP 3.0, did you correctly upgrade?

http://developersmind.com/2010/06/17/upgrading-wordpress-mu-2-9-2-to-wordpress-3-0/

It also sounds like your BP install is corrupted. Here’s a guide to upgrade BP:

http://codex.buddypress.org/getting-started/upgrading-from-10x/