If you have an HTTP proxy server on your network, you may have to manually set in the application the proxy parameters with the hostname or IP address of the proxy server.
You may enter this info via the menu Tools > Options > Network Proxy. Access is allowed, even if the license software key is not yet activated.
The default setting is to use the proxy setting from you system/browser:
But if that fails, you should enter the hostname or IP address of the proxy server, and the appropriate port number. If the proxy server requires a user name and password, you may include your credentials as well: