Rosetta uses a cloud based licensing system from Nalpeiron. If you are operating Rosetta within a corporate firewall, you will need to allow access to nalpeiron.com and also my.nalpeiron.com by adding these to your firewall's whitelist.
Nalpeiron’s software licensing and analytics platform sends all traffic over TCP Ports 80 and 443 (using secure 256-bit AES encryption) in order to ensure activations using the service are as accessible as possible to end-users.