"The IIS Express settings are missing the App Url property" when trying to configure ASP.NET 5 project

Question

I downloaded a sample ASP.NET 5 (vNext) application and tried to configure it to run on my local machine.

When I opened the Project Properties window and switched to the Debug tab, the App URL field is empty and cannot be edited:

When I try to change from IIS Express to the web profile, or even close the Properties window, I get this error:

The IIS Express settings are missing the App URL property. This is required to configure IIS express to run the site.

At this point, Visual Studio is totally stuck, and won't even quit. I had to kill the process via the Task Manager to get out.

How can this property be set if the field is locked?

Answer 1

The project was missing the iisSettings section in Properties\launchSettings.json.

The original launchSettings.json:

{
  "profiles": {
    "IIS Express": {
      "commandName": "IISExpress",
      "launchBrowser": true,
      "environmentVariables": {
        "ASPNET_ENV": "Development"
      }
    },
    "web": {
      "commandName": "web",
      "environmentVariables": {
        "ASPNET_ENV": "Development"
      },
      "sdkVersion": "dnx-clr-win-x86.1.0.0-rc1-final"
    }
  }
}

I had to add this section above profiles:

"iisSettings": {
  "windowsAuthentication": false,
  "anonymousAuthentication": true,
  "iisExpress": {
      "applicationUrl": "http://localhost:49901/",
      "sslPort": 0
  }
}

After adding this, I was able to modify the settings normally via the Properties window.