[asp.net-mvc-2] A default document is not configured for the requested URL, and directory browsing is not enabled on the server

This can also occur if you do something stupid (like I did) and place the api url in the "Project Url" (e.g. http://localhost:59088/api/Product) on the Project Properties->Web tab instead of specifying it in the "Specific Page" text box. This causes Visual Studio to go ahead and create an APP called ProjectName/api/Product, and this will expect a default page. The only way to undo this is to go to C:\Program Files (x86)\IIS Express and use appcmd.exe to delete it like so

>.\appcmd.exe delete APP "ProjectName/api/Product"