SAML Assertion Not Passed from Azure to Marketo

Issue

You are following the SSO setup instructions provided by Azure to configure your IDP (https://docs.microsoft.com/en-us/azure/active-directory/active-directory-saas-marketo-tutorial). However, you are getting the error message: " Error processing SAML message. Request was ill-formed in some way. " To troubleshoot that message you are collecting the SAML assertion being passed to Marketo to identify potential issues with it (as described here: https://docs.microsoft.com/en-us/azure/active-directory/develop/active-directory-saml-debugging ). However, when trying to capture the SAML, you are not able to find any SAML in the network tracer even after arriving at the error message. 
 

Solution

Confirm the field "Sign on URL" is empty as it is only intended to be used for service provider initiated single sign-on, which is not supported by Marketo. 

Disclaimer: Marketo does not support 3rd party products such as Azure Active Directory and cannot configure your IDP on your behalf. This document is intended to assist Azure users in configuring their IDP, but no guarantees are made that this information is accurate.