How registration works for SEFAUtil Server:
When a key is requested, a trial period for all features will be created for 30 days.
Set-SefautilServerRegistration –Name YourOrgName –EmailAddress[email protected] –PhoneNumber YourPhoneNumber –Implement{Press {Tab}
If the server doesn't have internet access, you can manually get a trial key by emailing [email protected] and requesting one.
More details on installing & registering SEFAUtil Server:
http://windowspbx.blogspot.com/2016/03/how-to-install-skype-for-business.html
How to register SEFAUtil Server after you have a registration key:
Set-SefautilServerRegistration –RegistrationKey “{key here}