AD FS IdP Error while logging out from IdP

[Cantor, Scott]

What Todd said. But I'd add that there is no WS-Fed query parameter involved in the ADFS SAML logout endpoint, I have metadata for ADFS systems and the endpoint is bare, no parameters. I doubt that's helping matters, and likely something you misconfigured in the metadata given to the SP and causes ADFS to apply the wrong message handling requirements.

-- Scott