Is it possible to force users to login in order to see KB content?

Yes, this facility in present in version 7 of PHPKB knowledge base software so that you can restrict the access to knowledge base for only logged in users. Please refer to the steps below to enable that setting.

  1. Login to the admin control panel.
  2. Go to "Tools" » "Manage Settings" page.
  3. There is a setting called "KB Access" as shown in the image below.

    Restrict Access to Knowledge Base

  4. You can set it as "Restricted” so that only logged in users can access the KB.