Office365 Exchange protocols with APM and SAML

Ah..... now that rings a bell.

The flow is fairly simple - OutlookAnywhere are using Basic Auth to connect to Office 365. When those credentials are presented to O365, it suspends the connections and makes SAML ECP-based AuthN request(SOAP-wrapped AuthN request) to the IDP. The IDP authenticates the user(the user's Basic credentials are passed to the IDP) and return a SAML assertion response - if it is positive, the O365 allows the connection to go through to the backend and allow access to that user's account.

I've seen an old doc from Microsoft that described that flow, but I can't find it now..... Let me know if you really need it and I can dig it up.