It is important to note that the machine dedicated as CodeMeter Network Server will access to TCP port 123 for NTP timeserver updates.
If your firewall restricts access to NTP servers you need to create a firewall rule to allow access for the CodeMeter host to access the NTP time server below:-
cmtime.codemeter.com [62.96.20.199]
These additional time servers can be added to a group rule to allow for redundancy in the event of one or more CodeMeter time servers being unavailable.
cmtime.codemeter.de [62.96.20.199]
cmtime.codemeter.us [74.93.98.100]
cmtime.codemeter.fr [217.128.103.34]