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Create groups to organize your subscribed users and send them e-mails based on their groups or by user levels, capabilities or usernames. You can also send messages for anybody, directly by e-mail addresses. Besides that, you can use some information of the current user and of a selected publication (post or page), to personalize the message, that can take attached files, if you want. WPMailing offers support if you are using Xinha4WP or Dean’s FCKEditor, to write e-mails in your favorite editor.
<h3>Features</h3>
Once the plugin is activated, your administration panels will offer:
<ul>
<li>The ability to create groups and tag your users, by adding new features in Users section pages 
through Javascript (user.php, profile.php and user-edit.php). 
** This actions will not modify the WP original files.</li>
<li>An interface to modify names and descriptions of your groups (Manage > Groups) </li>
<li>An interface to compose and send e-mails to subscribed users, 
with some interesting features (Write > Write e-mail): 
** The ‘To’ field supports multiple e-mails and inclusions by user level, capability, group or username. 
** You can attach multiple files to the message 
** You can use values of an specific post or page 
** The e-mail can be personalized with informations of the user that will receive the message</li>
<li>An interface to set or update some WPMailing configurations (Options > Mailing) </li>
<li>Complete information about the sending process after you send any e-mail</li>
</ul>
<h3>Feedback</h3>
Your feedback are welcome. 
 Send any bug detections, suggestions, critics, etc. to: wpmailing(at)jsbrasil(dot)com 
 Thank you, Cau Guanabara.

WPMailing

Create groups to organize your subscribed users and send them e-mails based on their groups or by user levels, capabilities or usernames.

Robin W

An add-on to the bbPress forum plugin – creates private forum groups
This Plugin creates unlimited private forum groups.
Forums are then allocated to one or more groups, and users allocated to one or more groups.
What this achieves 
unlimited private groups 
Each user is set to a group or groups, and each forum can have any or all the groups associated with it 
Any number of public forums combined with any number of group forums. The group forums can be individually set to public or private. 
Forum title and description (but not topics or replies) can be set to be visible to non-group users, allowing people to see that a forum exists but not access it 
Separate pages can be set to allow redirection of non group users for sign-up or information 
Topic Permissions 
Topic Permissions is designed for sites where users need to have different permissions to different forums. 
For instance the ability for users to contribute to one forum whilst only being able to view another, or only start topics in one forum, or only reply to topics in another.
Example
So if 
User a belongs to group 1 
User b belongs to group 2 
User c belongs to group 3
and 
Forum x is set to allow group 2 
Forum y is set to allow group 2 and group 3 
Forum z is set to allow group 1 and group 3
Then 
User a can access only forum z 
User b can access forum x and forum y 
User c can access forum y and forum z
Restrictions/warnings
The widgets (bbpress) forums list, (bbpress) recent replies, and (bbpress) recent topics SHOULD NOT BE USED, as they will show topics headings and author names for all forums. Replacement widgets called (private groups) forums list, (private groups) recent replies, and (private groups) recent topics are available instead
Works with bbpress 2.5.3 or higher

Private groups

After wasting hours trying to get Skyverge's WooCommerce Memberships to do what I needed (no practical way to protect topics), I tried this and had it doing everything I needed in under 15 minutes.

Setup a group, manually assigned users to that group.
Set the forum to private and assigned that that group to it.
Viola, everything worked exactly as I wanted.

Public doesn't even see the forum exists. Group members can when logged in.  Non-members can't go directly to to topic URL and bypass the protection.

Only suggestions would be:
1. cleanup the settings pages and instructions, they're a bit overly complicated and hard to follow. 
2. some way to trigger group membership programmatically based on a WooCommerce purchase (I know, to specific and I'll probably code it myself for what I need).

Thanks again for an awesome bbp plugin!

Easy setup and protected forums exactly as I needed

For bbPress - Creates private forum groups

WPMailing vs Private groups