Error "The sign-in was unsuccessful. Try again." Occurs When Attempting To Sign In To The SAML-Enabled Tableau Online Site

Issue

When attempting to sign in to Tableau Online, the following error occurs:

The sign-in was unsuccessful. Try again.
If you continue to get this message, capture the status information below, and send it to Customer Support.

Environment

Tableau Online
SAML

Resolution

Solution:
Make sure the assertions sent by IdP match the assertions Tableau Online expects.

Example (Azure AD): If you’ve configured Microsoft Azure Active Directory (Azure AD) as your SAML identity provider (IdP), the assertion will be the following
http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress or http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name
For more information see Match assertions (Azure AD).
User-added image

Workaround:
Revert the user account to TableauID instead of SAML Authentication. See Set the User Authentication Type.

Cause

Login failed because the mapping of assertions is incorrect. The site admin needs to either choose the correct attribute or set the User Authentication Type to TableauID.