"Check for Available Renewals" may show error banner "citrixservices.citrix.com is unreachable"

When user clicks "Check for Available Renewals" button in Citrix License Server Console, error banner "citrixservices.citrix.com is unreachable. The server might be offline or there might be Internet, Proxy, or Firewall issues. " may appear. Actually, the affected license server is able to reach...