You need your firewall to let TCP / UDP
443 / 80 / 3389
ports opened for ingoing and outgoing traffic.
These are the IP addresses to open at the level of software and hardware firewalls:
188.8.131.52 : License / telemetry
184.108.40.206 : Updates
220.127.116.11 : TSplus compatibility updates / Check for updates / View changelog
These are the URLs to allow for updates: