yep I had this same issue but in a webforms u 4.11 site.

I've stumbled on a different workaround, a little strange but seems to work

I have the 404 page set in the umbracosettings and that serves fine for aspx pages (status code is 404)

however, I could only get a status code of 200 setting the httperrors...

So what I did was web.config, 

I didn't add the <customErrorsmode="On"defaultRedirect="~/404.aspx"/>

but in the httperrors

<httpErrors errorMode="Custom"> <remove statusCode="404" subStatusCode="-1" /> <error statusCode="404" prefixLanguageFilePath="" path="/5820.aspx" responseMode="ExecuteURL"/> </httpErrors>

and here's the rub... the path value is an id that doesn't exist, so at that point umbraco handle404 should intercept and give the 404 page with a status of 200, but for some reason it still doesn't.

So I just recreated my own 404 handler and added to the 404handlers.config and that seems then to pick up and redirect to the 404 page with a 200 status code.

public class FidusCMS404Redirect : INotFoundHandler
    {
        private int _redirectID = -1;

        #region INotFoundHandler Members

        public bool CacheUrl
        {
            get
            {
                return false;
            }
        }

        public bool Execute(string url)
        {

            if (umbraco.UmbracoSettings.UseDomainPrefixes)
            {
                // we have multiple domains, try and map 404's
                XmlNode error404Node = UmbracoSettings.GetKeyAsNode("/settings/content/errors/error404");


                if (error404Node.ChildNodes.Count > 0 && error404Node.ChildNodes[0].HasChildNodes)
                {
                    // try to get the 404 based on current domain
                    XmlNode domainErrorNode;
                    string CurrentDomain = System.Web.HttpContext.Current.Request.Url.Host.ToLower();

                    // try match to domain
                    domainErrorNode = error404Node.SelectSingleNode(String.Format("errorPage [@domain = '{0}']", CurrentDomain));

                    try
                    {
                        _redirectID = int.Parse(domainErrorNode.FirstChild.Value);
                    }
                    catch
                    {
                        domainErrorNode = error404Node.SelectSingleNode(String.Format("errorPage [@domain = '{0}']", "default"));

                        try
                        {
                            _redirectID = int.Parse(domainErrorNode.FirstChild.Value);
                        }
                        catch
                        {
                            _redirectID = Convert.ToInt32(UmbracoSettings.GetKey("/settings/content/errors/error404"));
                        }
                    }

                }
                else
                {
                    _redirectID = Convert.ToInt32(UmbracoSettings.GetKey("/settings/content/errors/error404"));
                }

            }else{
                _redirectID = Convert.ToInt32(umbraco.UmbracoSettings.GetKey("/settings/content/errors/error404"));
            }            

            umbraco.BusinessLogic.Log.Add(umbraco.BusinessLogic.LogTypes.NotFound, _redirectID, "404 Redirect - " + HttpContext.Current.Request.Url);
            //301 rather than just 404
            //HttpContext.Current.Response.Status = "301 Moved Permanently";
            //HttpContext.Current.Response.AddHeader("Location", umbraco.library.NiceUrl(_redirectID));

            return true;
        }

        public int redirectID
        {
            get
            {
                //return 1983;
                return _redirectID;
            }
        }

        #endregion
    }

Sort of a double take.. but seems to work.

Not sure if this approach is posible in MVC... ???  

I ended up hijacking the route with a custom controller, when i set the 404 status in the custom controller and then outputting the view, i both get content and the correct status code.

I ended up hijacking the route with a custom controller, when i set the 404 status in the custom controller and then outputting the view, i both get content and the correct status code.

I did this due to testing the whole setting the statuscode on the razor page for another page, and i got exactly the same issue..

So what i did was a Custom controller for the error page..

    publicclassCustomErrorController : RenderMvcController

    {

        public ActionResult Index(RenderModel model)

        {

            Response.TrySkipIisCustomErrors = true;

            int statusCode = 404; // Default

            if (model.Content.GetProperty("errorStatusCode") != null && !string.IsNullOrWhiteSpace(model.Content.GetProperty("errorStatusCode").Value.ToString()))

            {

                statusCode = int.Parse(model.Content.GetProperty("errorStatusCode").Value.ToString());

            }

            Response.StatusCode = statusCode;

            return base.Index(model);

        }

    }

(Why can't i mark the above as code??)

This allows me to set it pretty easily, i can also easily make a corresponding error 500 page, but with a different template for another text, but using the same document type to route it through the controller..

Thanks anyway for your extensive response Mike :)

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