Not passing a UID or NAME ID from ADFS claim rules
In ADFS the Relying Party Trust needs to have a Claim Rule that Passes either a UID or a NAME ID value. Workfront Test Connection will show this if successful.
ADFS INFO: In the Relying Party Trust object > Claim Rule
LDAP Attribute (Left column) should have E-Mail Addresses (or any unique identifier).
Outgoing Claim Type (Right column) should be Name ID.
It doesn't have to have the LDAP Attribute E-Mail Addresses; any unique identifier that will identify the user can be used but it must be passed into Workfront as the NAME ID.