ASP.NET MVC showing error page on when sending responses with status 500

Question

I have the following action in the server:

[HttpPost]
public JsonResult SearchContracts(SearchViewModel vm)
{
    List<string> errors;

    if (IsValid(vm, out errors))
    {
        return Json(service.Search(vm), JsonRequestBehavior.AllowGet);
    }
    else
    {
        HttpContext.Response.StatusCode = 500;

        return Json(new { Errors = errors }, JsonRequestBehavior.AllowGet);
    }
}

Locally, it works great. When the request is not valid, it returns a JSON with the errors and the response has a 500 for the HTTP status code.

When deployed, instead of the JSON described, IIS is returning me this famed error page.

Here is the web.config with the detail for the customErrors section:

<customErrors mode="Off" defaultRedirect="~/error.htm">
    <error statusCode="404" redirect="~/errorhandling/pagenotfound" />
</customErrors>

I tried turning it to On but neither worked.

Where should I change to stop recieving that ugly error page instead of my beauty JSON?

Edit:

I changed the status code to 400, now I am getting the text Bad Request as a response, instead of the JSON:

Bad request text

Simple dont use the dark error 500 to notify invalid state of models to users, it is intended to be used when something was wrong in the server side but the server itself is unable to tell you what was wrong. For example access was denied when accessing a mail server or something alike. — E-Bat, Jan 05 '15 at 16:50

score 8 · Accepted Answer · edited May 23 '17 at 12:08

8

From this link:

Solved editing the web.config and adding the following attribute:

<system.webServer>
    ...
    <httpErrors existingResponse="PassThrough"></httpErrors>
    ...
</system.webServer>

Another bizarre Microsoft story.

edited May 23 '17 at 12:08

Community

1
1

answered Jan 05 '15 at 19:58

lante

7,192
4
37
57

score 2 · Answer 2 · answered Jan 05 '15 at 16:29

2

You are using server error instead of client error. According to Wikipedia for 5XX errors:

"The server failed to fulfill an apparently valid request."

In this case your server works fine and the client send bad request. Use clients errors (4XX) instead.

answered Jan 05 '15 at 16:29

Sam FarajpourGhamari

14,601
4
52
56

I edited it, but now I am getting the text `Bad Request` :( Please see my question updated – lante Jan 05 '15 at 19:33

score 1 · Answer 3 · answered Dec 28 '17 at 13:37

Here's what to do if you need to use both Custom Error Pages and sometimes return custom data for http statuses defined in httpErrors section: - set existingResponse="Auto" in web.config (httpErrors section, that's where you define Custom Error Pages); - set TrySkipIisCustomErrors = true in your action (one that returns 4xx status and a content); - clear server error in global.asax (in Application_Error() - Server.ClearError()) and re-set the status code (Reponse.StatusCode = ((HttpException)Server.GetLastError()).GetHttpCode())

ASP.NET MVC showing error page on when sending responses with status 500

3 Answers3

Linked