BuddyPress.org

@angelfire4xx The ‘Invite anyone’ plugin was originally written to extend the default send group invites to other members but that only allowed sending invites to join a group to people already on your personal friends list, ‘Invite Anyone’ changed that so it was possible to access a full site member list to invite from. Boone then […]

@angelfire4xx you install buddypress plugins like normal wordpress plugins – in the wordpress plugins directory.

Also, I have never used this plugin but I believe its functionality was rolled into Invite-Anyone https://wordpress.org/extend/plugins/invite-anyone/