Status of the "Join group" and "Leave group" of buddypress groups is not changed When object cache is enabled. That is when I go to the group profile and click the join group button; even I joined to the group, still button label is displayed as "Join group". When I disable the object cache from the general settings of w3 total cache, problem is solved.
But I would like to know how to disable object cache for buddypress groups only with enabling object cache for other components of the site.