One of the security measures you can take with a multi-site Wordpress installation is to limit registered users to a specific set of domains. You can also ban specific domains so that users can't purposefully log into your website. The following article explains how to set the limiting email registrations and banned email domain options within the Network Admin of a Wordpress installation.
Setting Email Registration Limits in a Multi-Site Wordpress Installation
- Login to the Network Admin for a Wordpress MS Installation.
- Scroll down the left hand menus until you find SETTINGS. Hover over SETTINGS then click on NETWORK SETTINGS when it pops up on the right.
- If you wish to limit email registrations so that only specific domains can register, then click in the Limited Email Registrations field. Registrations will only be allowed for the domains listed here.
- Immediately below that is the Banned Email Domains section. Type in the domain names you do NOT want to have access to your Wordpress MS site.
- When you have completed entering the domain settings, scroll down to the bottom of the screen and click on SAVE CHANGES in order to save your entries.
This completes the tutorial on limiting email registrations for your Wordpress MS site. Remember that these settings can possibly prevent legitimate users from logging in to make comments on your website. If you need further information on your networked Wordpress installation, please go to Wordpress Education Channel.