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 Subscribe2, this plugin allows registered and unregistered users to be notified via email whenever there is a new post that they are permitted to access. Users can choose between different email contents and post categories.
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://subscribe2.wordpress.com/plugin/" rel="nofollow ugc">Subscribe2</a> plugin allows registered and unregistered users to be notified via email whenever a new post is published, regardless of whether access is restricted. It allows users to subscribe to either full posts or excerpts of posts, to choose whether the format of full posts should be HTML or plain-text, and to select which categories they are interested in.
Our version of the plugin works with <a href="https://wordpress.org/extend/plugins/social-access-control/">Social Access Control</a> so that users receive emails only for posts or categories of posts that they are permitted to view. In addition, the administrator can choose from several email contents depending on whether the post is public or restricted: full post, excerpt, title only, or no email.

Subscribe2 for Social Privacy

Based on the 3rd-party Subscribe2, this plugin allows registered and unregistered users to be notified via email whenever there is a new post that the …

Private BuddyPress vs Subscribe2 for Social Privacy