This error message appears only if a user is not logged in or is using a private browser window.
Cause
Most likely, the plugin “Members” installed and activated.
Members has enabled the „Content Permissions“ feature. This allows you to specify, on a post-by-post basis, which roles are allowed to view the content.
Users who do not have any of these roles will see the error message “We’re sorry, but this content can only be viewed with sufficient permissions” instead of „the_content()“—that is, instead of the content.“
Solution / Workaround
Open the post or page and uncheck all the boxes in the “Roles” field:
