We have been tasked with enabling SSO for OWA as we begin planning our transition from Exchange 2010 to O365 and can't get it to work. After much research and trial and error I came across this little gem:
"Integrated Windows authentication can be set only on Exchange 2010 virtual directories on an Exchange 2010 server that has only the Client Access server role installed. Integrated Windows authentication can be set on any Outlook Web App virtual directory on an Exchange 2010 server that has both the Client Access and Mailbox server roles installed."
If I am understanding this correctly, we cannot use IWA, because we have both CAS and HT roles on our CAS boxes. So my question is: Is there any way to get SSO working with our current configuration?