IIS Express Enable External Request - 503

Question

I have attempted to get IIS Express working so that external users can view my MVC ASP.NET development website. I followed instructions on this SO answer but am now getting a 503 error when accessing the website using my external IP address, localhost still works fine.

My configuration file seems ok

<site name="ManagerUI" id="5">
    <application path="/" applicationPool="Clr4IntegratedAppPool">
        <virtualDirectory path="/" physicalPath="D:\Application Development\Manager\MAIN-Branch\ManagerUI\ManagerUI" />
    </application>
    <bindings>
        <binding protocol="http" bindingInformation="*:1904:" />
    </bindings>
</site>

I found the following SO answer which solves the issue, but it will ONLY allow it to work on an external address rather than all my IP addresses (localhost, external one etc)

<binding protocol="http" bindingInformation=":1904:your-machine-name" />

Solution

I managed to solve it, my mistake was thinking that you could only have one binding set, I then setup binding for every external address I wished to serve on and it now all works

<bindings>
    <binding protocol="http" bindingInformation=":1904:" />
    <binding protocol="http" bindingInformation=":1904:machineName" />
    <binding protocol="http" bindingInformation=":1904:10.1.10.123" />
</bindings>