according to the blog How To Install ADFS (Part 1 + 2), I did setup a ADFS Server and a ADFS Proxy, both based on Windows Server 2012 R2.
I can achieve the federationmetadata.xml page both from internal and external network regardless whether using a domain user or using a workgroup user. So far, so good.
But trying to achieve the /adfs/idpInitiatedSignOn.hml page only succeeds, if I connect from the internal network as a domain user. Trying to access this page failes with HTTP error 503 (Service Unavailable), if I want connect from external network. The same issue occurs if I try to connect from internal network as a non-domain user.
Unfortunately there are no entries in the event log referring to this issue. Has anyone an idea what happens in my environment?
Regards
Enrico