Guest Users Being Prompted For Sign In On Tableau Server

Issue

When guest users who are already authenticated to Tableau Server attempt to open a dashboard on a Site with enabled guest access, which is not the Site they were previously logged into, they are being prompted for Tableau Sign in. When signing in, the following error message will occur:

You're not a member of this site or this site does not exist. For help, contact your Tableau Server administrator.

User-added image

This happens when the user is also a member of another Site in Tableau Server and they access their account/Site before using the embedded link or Share URL for the guest Site view.

Environment

Tableau Server v2021.2, v2021.3, v2021.4

Resolution

Workaround

Sign out of the Tableau Server account accessing the other non-guest Site and open the guest Site dashboard link.
Close the browser window and re-open before using the guest Site dashboard link.

Cause

This is a known issue currently under investigation with ID 1413011.

Additional Information

For the issue to happen the user needs to have normal access to at least one Site on this Tableau Server environment, and be accessing content from a different Site they do not have access to.