NTLM passthrough broken

Hello,

recently I stumbled into an issue, that new clients would not connect to our RDWeb server through RemoteApp- and desktop connections.

As they are able to connect using the internal FQDN, but not using the external domain name throwing an 401.2 error, it seems that the reverse proxy breaks the NTLM authentication with the remote desktop webserver although I'm not using reverse authentiaction.

Are you having these issues, too?