Dennis

Protect your BuddyPress Installation from strangers. Only registered users will be allowed to view the installation and all other users will be redirected to the login page. Users attempting to view blog content via RSS are also authenticated via HTTP Auth.
You can exclude the registration, the homepage and blog pages (e.g. posts, archives and non-buddypress pages) from protection. In combination with the plugin ‘Invitation Code Checker’ your installation stays private but the registration is for users with a special password open.
The plugin includes a German and Hebrew (thanks to gstupp) translation.

Private BuddyPress

Protect your BuddyPress Installation from strangers. Only registered users will be allowed to view the installation.

Based on the 3rd-party Category Access, this plugin provides the core functionality for restricting the access permissions of posts. This gives you the ability to permit only specific registered users to read certain posts or certain categories of posts.
This plugin is part of the <a href="https://wordpress.org/extend/plugins/social-privacy/">Social Privacy</a> set of plugins and it’s recommended that you install the entire set at one time to get complete control over access to your posts on your blog.
<h4>Differences between the original plugin and our plugin</h4>
The 3rd-party <a href="http://www.coppit.org/blog/archives/173" rel="nofollow ugc">Category Access</a> plugin provides the core functionality for restricting the access permissions of posts to certain registered users. For each user you can list the categories that he or she should have access to.
New features have been added to our version of this plugin to allow access to be restricted to specific users on a per-post basis, regardless of the categories. The plugin has also been enhanced to work well with the other plugins in <a href="https://wordpress.org/extend/plugins/social-privacy/">Social Privacy</a> set, which add similar restriction capabilities to email and feeds.
If you decide to stop using this plugin, there is an additional feature that lets you make all your protected posts “private” so that they’re not suddenly exposed to the public once the plugin is deactivated.

Social Access Control

Based on the 3rd-party Category Access, this plugin provides the core functionality for restricting the access permissions of posts.

Private BuddyPress vs Social Access Control