Sometimes it happens that you want to browse to a website running on a server which is located at the same local network, but instead of typing in the URL to the website, you want to access it by IP and port number. This especially can be very handy if you want to run a testwebsite or development environment. But be aware that by opening up the port in the firewall, you have to change the profile to "private", or your website will not be accessible.
As we discovered the hard way, when we wanted to do this on a home server running IIS. We had set up a temporary site for something to test, so there was no domain name to browse to. Normally this shouldn't be a problem. Whack in the IP address of the server in your browser, and the custom port.
We opened up the port in the firewall, but still we could not get a connection. After some painful hours it became clear the default profile the firewall rules apply to is the "Public" profile. Never ever we had looked at the advanced tab, because opening a port always worked without any further finetuning. We never paused by the fact that we always opened up ports to the internet.
But when you want to open up a port to a local network, you have to choose the private profile. Hopefully you will be saved from hours of needless searching.