Membership Lock down will lock all post content including attached images, video, docs, and everything else, everywhere.
All who try to visit the site will be redirected to the login page.
The administrator can enable and disable the lock down as needed. 
Only registered website users will be able to access,
If a user is not logged in we will redirect them to the login page.

Membership Lock

Membership Lock down lets you easily lock all post content including attached images, video, docs, and everything else.

turtlepod

<a href="http://genbumedia.com/plugins/fx-private-site/" rel="nofollow ugc">f(x) Private Site</a> is a very simple plugin to set the site to members only website.
After installation of this plugin, you can enable this in “Settings > Reading” in “Private Site” Section.
Features:
<ol>
<li>Super simple.</li>
<li>Integrate to the WordPress “Reading” Settings seamlessly.</li>
<li>Also protect RSS Feed content.</li>
<li>Useful to set site private before lauching the site.</li>
<li>The GPL v2.0 or later license. 🙂 Use it to make something cool.</li>
<li>Support available at <a href="https://genbumedia.com/contact-us/" rel="nofollow ugc">Genbu Media</a>. 
Notes for developer: </li>
</ol>
<h4>Github</h4>
Development of this plugin is hosted at <a href="https://github.com/turtlepod/fx-private-site" rel="nofollow ugc">GitHub</a>. Pull request and bug reports are welcome.
<h4>Options</h4>
This plugin save the options in single option name: <code>fx-private-site</code>.

f(x) Private Site

Set your site to member only. All visitor will need to login to view site.

Membership Lock vs f(x) Private Site