Prefix uses Cryptlex for licensing. Some networks may require that you Whitelist Cryptlex IP addresses to enable LexActivator license and trial activations through the firewall.
Access through firewall
If your policy denies access from external IP addresses and websites, you will need to whitelist the IP addresses below. A whitelist provides access to designated IP addresses and sites that would otherwise be prevented by your security policy.
52.223.22.71
35.71.188.31
Alternatively, you can also whitelist Cryptlex Web API URL:
https://api.cryptlex.com:443
Additional domains you may need to whitelist:
https://prefix.azureedge.net/