Content Restriction consists of two parts: Restricting Pages, and Restricting Media Content.
When creating a new page, or editing an existing page, you’ll notice below the content box is a box titled Restrict Access to this Page, which looks like this:
If you want to restrict the page you’re currently working on, select the checkbox, and select the group that you want to allow access to from the drop-down menu. Once selected, be sure to Update the page. If the page is not updated, the changes will not take effect.
When you restrict access to a page that is a parent (i.e., the page has children), that restriction is applied to all child pages as well.
If you need to remove restriction to a page simply uncheck the Restrict access to this group checkbox, and re-update your page.
Please note: the Access Restriction tool is only available on pages in WordPress, and not posts.
Restricting Media Content
If you want to restrict media content (images, PDFs, docs, AVI files, etc.), but don’t want to restrict access to an entire page, you can use the Media Content Restriction.
To restrict a specific piece of media that you’ve uploaded, you’ll need to log in to your WordPress Dashboard, select Media, and then select Library.
Select the piece of media you want to restrict by clicking on the file name under the File column.
On the Edit Media page, simply check the checkbox next to Restrict access to this group and select the group you want to allow access to from the drop-down.
When done, click Update Media.
If a file is protected, you’ll see the Lock on the Media Library list of media items.
If an image is protected, the page where it is displayed will show a broken image in its place.
If another piece of media is protected (AVI file, mp3, etc.), an unauthorized person will not be able to download it.