Hey everyone, This isn't a "how does it work" question but rather "it's broke and I don't know why". Please let me know if this is off-topic here. I have an instance of SATOSA deployed using mod_wsgi. The BASE variable in proxy_conf.yaml is set to something like `https://federation.example.com/satosa`. Everything works until my test IdP returns the SAML authentication response to SATOSA at `https://federation.example.com/satosa/Saml2/acs/post`, where it returns a 404 error. In the logs, I see the following: [Thu Feb 22 16:47:49.219942 2018] [wsgi:error] [pid 9824] [remote ...] [2018-02-22 16:47:49,219] [DEBUG] [satosa.proxy_server]: unpack_post:: {'RelayState': '...', 'SAMLResponse': '...' [Thu Feb 22 16:47:49.231630 2018] [wsgi:error] [pid 9824] [remote ...] [2018-02-22 16:47:49,231] [DEBUG] [satosa.state]: [urn:uuid:3bb9c05d-b665-4c23-9a89-8affc05d4574] Loading state from cookie: SATOSA_STATE='...'; ... [Thu Feb 22 16:47:49.231816 2018] [wsgi:error] [pid 9824] [remote 10.63.1.38:51166] [2018-02-22 16:47:49,231] [DEBUG] [satosa.routing]: [urn:uuid:3bb9c05d-b665-4c23-9a89-8affc05d4574] Routing path: Saml2/acs/post What am I missing? How do I go about troubleshooting this further? Best wishes, Matthew -- "The lyf so short, the craft so longe to lerne."