Windows – Can’t connect to local IIS on Windows 8

I'm pretty sure the firewall doesn't block/inspect the localhost/loopback address (127.0.0.1) because it's your computer. So since the target and source are the same, there's really nothing to firewall.

When you enabled port 81, or fully disable the firewall could you then access the 2nd site? If not, you may have an IIS configuration problem, and not a firewall problem.

The short answer is that you go to the Programs and Features control panel applet. Then click on Turn Windows Features On and Off and enable the assorted IIS-related features you need.