As part of the connector install it checks that it can reach https://api.agilicus.com/ with proper encryption. Some sites use an Actor In The Middle SSL inspecting firewall, these redirect port 443 to themselves and send a different certificate back. This prevents end to end encryption from operating safely.
On a site with one of these security appliances, you can either configure the connector to participate with the proxy (by setting http_proxy environment variable), or, configure the security appliance to not redirect the traffic for the IP of the machine the connector is on.
You can confirm the certificate chain issue by running:
openssl s_client -showcerts -servername api.agilicus.com -connect api.agilicus.com:443 </dev/null | more