I have a Federated custom O365 AzureAD domain with On-premises Active directory domain .Azure AD Connect is used to integrate on-premises directories with Azure AD. The integration with O365 is done with third party multi-factor authentication server using SAMl 2.0 and not used ADFS for the sso to integrate with on-premise AD DC with Azure AD . So, while i login with O365 user ( synced from on-premises AD domain in the O365 cloud), it will ask for the 2F authentication and suppose to land in to the users home page but it fails and browser throws error "Sorry, that didn’t work. Please go back to office.com and try again” Any help in resolving the issue is higly appreciated . Attached the url error and SAML trace for your reference . ![77299-o365auth-error.jpg][1][77363-saml-office-365-error-direct-without-adfs.txt][2] [1]: /answers/storage/attachments/77299-o365auth-error.jpg [2]: /answers/storage/attachments/77363-saml-office-365-error-direct-without-adfs.txt