From the Knowledgebase

How to Upgrade your Site to the Secure Version

A couple notes when upgrading from the Premium to the Secure plugin:

  1. You will receive a new plugin download and license (available on your Purchase History dashboard). You must deactivate the Premium version of the plugin before you activate the Secure, otherwise you will receive a fatal error (only one version can be activated at one time),
  2. Any PDFs that you had previously uploaded to your site will need to be re-uploaded in order to have them placed in the "securepdfs" folder located in wp-content/uploads of your site (folder will be created automatically with the first upload).
    • You can move existing PDFs either by uploading again via the Add Media, or using FTP / your webhost's File Manager to move the files.
    • Additional steps to register the media files in the database after using FTP must be completed before the PDFs will appear in the Media library (tutorial article).
    • Any shortcodes already added to your content will need to be updated with the new file path.
  3. There is a set up guide specific to the Secure version of the plugin here: