CUNY Academic Commons

r-a-y

User registration spam is prevalent in BuddyPress.
One way to dramatically decrease signup spam is to restrict the email address domains that users can sign up with.
WordPress multisite has a native option called “Limited Email Registrations”. But this option requires you to enter the full email domain. For example, if you only wanted to allow .edu email addresses to register, this is not possible.
This plugin restricts registrations to the email domains that you specify and works in WordPress single-site and multi-site.
Plugin was developed for the <a href="http://commons.gc.cuny.edu" rel="nofollow ugc">CUNY Academic Commons</a>. Licensed under the GPLv2 or later.
<a href="https://github.com/cuny-academic-commons/bp-rsed" rel="nofollow ugc">Follow development on GitHub</a>.
Tested on BuddyPress 2.5, but should work all the way down to BuddyPress 1.6.

BP Restrict Signup by Email Domain

Only allow users with email addresses from certain domains to register in BuddyPress.

rich! @ etiviti

** IMPORTANT **
This plugin will not be updated for future versions of BuddyPress (1.3) – if you would like to take over this plugin, please contact me. 
http://twitter.com/#!/etiviti/statuses/29550143485247489
This plugin enables restriction of email domains during user registration for a single (non-multisite) WordPress installation of BuddyPress
This plugin will NOT work for a multisite/network WordPress install – intended for single WordPress ONLY.
<h4>Related Links:</h4>
<ul>
<li><a href="http://blog.etiviti.com/2010/09/buddypress-restrict-email-domains-plugin/" rel="nofollow ugc">Plugin About Page</a></li>
<li><a href="http://etivite.com" title="Plugin Demo Site" rel="nofollow ugc">Author’s BuddyPress Demo Site</a></li>
</ul>
<h3>Extra Configuration</h3>

BuddyPress Restrict Email Domains

This plugin enables restriction of email domains during user registration for a single (non-multisite) WordPress installation of BuddyPress

BP Restrict Signup by Email Domain vs BuddyPress Restrict Email Domains