Port 443 - Configure your firewall

Dot .Net Dilemmas
We were having some issues recently where a client could not register our software.
We got an email from them asking if we "used any any ports other than Port 80 or 8080 during the registration process?"
It turned out that they were behind a firewall where all ports were 'locked down' unless the firewall was specifically configured to allow them access. This meant that their firewall was blocking access to one of our web services but they weren't sure why. They had configured it to enable access to Port 80 and Port 8080 and assumed that this was all that they needed to do.

As part of our registration we use Port 443 for HTTPS calls (note the 'S' at the end.) Using a HTTPS URL indicated that HTTP is to be used but with a different default TCP Port - Port 443. Port 443 an additional encryption/authentication layer between the HTTP and TCP and is widely used for security-sensitive communication such as payment transactions and corporate information systems. Port 80 is typically used for unsecured HTTP calls. They configured their firewall to enable communication through Port 443 and so far so good, all registrations have gone through.

You can check the Ports used by opening IIS and clicking on 'Web Sites'. The Ports will be displayed against your various web sites in the right hand pane.