Visual Studio 2015: Custom Domains in IIS Express - Invalid Hostname

Question

I upgraded my ASP.NET MVC project to use Visual Studio, and the nasty Bad Request - Invalid Hostname error appeared. This problem has been documented in the past for previous versions of Visual Studio (e.g. Using Custom Domains With IIS Express), but I can't seem to find a solution for Visual Studio 2015.

I use many custom domains (e.g. http://foo.testsite.local:1299) to run my site. I run Visual Studio as an administrator and my bindings in applicationhost.config looks like this:

        <bindings>
          <binding protocol="http" bindingInformation="*:1299:" />
          <binding protocol="https" bindingInformation="*:44300:" />
        </bindings>

This worked perfectly fine in Visual Studio 2013, but for some reason, running my ASP.NET MVC app in Visual Studio 2015 returns:

HTTP/1.1 400 Bad Request

Bad Request - Invalid Hostname

Any workaround? I need to use wildcards in the bindings instead of hard-coded URLs, because my app supports multiple domain names (including custom subdomains).

I should note that http://localhost:1299 does work with these settings.

Answer 1

By default, VS 2015 solutions no longer use the applicationhost.config file from your users folder. Instead, they create one on the fly in the .vs\config folder under the solution. If you want to use the global file from your users folder, set the following property in your project file(s). It is a per project setting.

<UseGlobalApplicationHostFile>
    true
<UseGlobalApplicationHostFile>