IIS 7 can’t run ASP.NET MVC application due to missing System.Web.Helpers

In ASP.NET MVC you don't browse to your view files directly. You have to use the routes that are setup in your site's Application_Start() event.

For example, a new ASP.NET MVC project adds this route by default in global.asax:

routes.MapRoute(
    "Default",
    "{controller}/{action}/{id}",                           
    new { controller = "Home", action = "Index", id = "" }  
);

It also adds a default controller and action:

public class HomeController : Controller {
  public ActionResult Index() {
    ViewData["Message"] = "Welcome to ASP.NET MVC!";
    return View();
  }
}

And a View under Views/Home named Index.aspx.

Instead of using the address http://mysite.com/Views/Home/Index.aspx you would use http://mysite.com/Home/Index

You can learn more about routing here: http://www.asp.net/learn/mvc/#MVC_Routing

From my experience with ASP.NET MVC, I've seen that a Default.aspx page is required for IIS to function correctly. I'm using the page that was included in the ASP.NET MVC 1 template. Unfortunately, the ASP.NET MVC 2 does not include this page (to the best of my knowledge), so you should add the following to your project:

Default.aspx:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="YourNamespace._Default" %>

<%-- Please do not delete this file. It is used to ensure that ASP.NET MVC is activated by IIS when a user makes a "/" request to the server. --%>

Default.aspx.cs:

using System.Web;
using System.Web.Mvc;
using System.Web.UI;

namespace YourNamespace
{
    public partial class _Default : Page
    {
        public void Page_Load(object sender, System.EventArgs e)
        {
            // Change the current path so that the Routing handler can correctly interpret
            // the request, then restore the original path so that the OutputCache module
            // can correctly process the response (if caching is enabled).

            string originalPath = Request.Path;
            HttpContext.Current.RewritePath(Request.ApplicationPath, false);
            IHttpHandler httpHandler = new MvcHttpHandler();
            httpHandler.ProcessRequest(HttpContext.Current);
            HttpContext.Current.RewritePath(originalPath, false);
        }
    }
}