Issue: RDP Relay to Windows 10 or Windows 2016 fails with an error the connection cannot proceed because authentication is not enabled. This issue occurs when the network level authentication is enabled in Windows 2016 or Windows10.
Workaround: To workaround this issue, change the Security Layer level to 0 or 1. You can find the Security Layer registry entry at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp.