I am trying to email with attachment links to a 3rd party (not a request participant) via automation so they can access the attachments without needing to login to the client portal. Initially they were getting a forbidden error when they clicked on the link, so I changed this setting inside the project.

That didn't fix the issue and they still received the "You do not have permission to view attachment with id...", so I created a new rule using the steps outlined in this article. They are no longer getting a forbidden error but they are being asked to log in to access the attachments.
Does anyone have a solution to this issue or know what I am missing?