I have TV installed on a WinSrv2016 machine. That machine has no restrictions on internet access. I can log into the TV management console, using my TV account.
However this machine just cannot - or will not - log into the "Computers and contacts" module of TV in the same Windows session. I enter the credentials (which work on management console). There is a delay, and then a message "the server could not be contacted".
Business licence is activated at this installation. EMUS is disabled. I logged in system thru RDP (as an ordinary user, but if as an admin -- no diference). TV service is running.