IIS7 Custom ASP.NET Errors

Question

I'm trying to setup a custom error page for the IIS 7 404.13 (Content length too large) error. Here's the relevant sections of my web.config file:

<system.webServer>
  <httpErrors errorMode="Custom" existingResponse="Replace">
    <remove statusCode="404" subStatusCode="13" />
    <error statusCode="404" subStatusCode="13" prefixLanguageFilePath="" path="/FileUpload/Test.aspx" responseMode="ExecuteURL" />
  </httpErrors>
  <security>
    <requestFiltering>
      <requestLimits maxAllowedContentLength="10240" />
    </requestFiltering>
  </security>
</system.webServer>

The response that is being sent back to the server is blank. The Test.aspx file is not blank.

Any idea what's going on here?

Answer 1

That looks correct. Do the IIS logs confirm that a 404.13 error was actually hit? You can test with a standard 404.0 page to confirm that the error pages work as expected. Another way to test that easier is to drop the maxAllowContentLength to a low setting and test with something smaller. That will give you faster feedback in your troubleshooting, and it will confirm that maxAllowedContentLength is the correct setting for the situation that you're testing.

Answer 2

Follow the steps as given here and you should be good.

Answer 3

I'm also getting a blank page (in MVC) when i try to ExecuteURL on a action. It works to use responseMode="Redirect" and setting path as an absolute URL.

See this post: http://stackoverflow.com/questions/2759193/display-custom-error-page-when-file-upload-exceeds-allowed-size-in-asp-net-mvc2/3787284#3787284

MSDN: http://msdn.microsoft.com/en-us/library/ms690497(VS.90).aspx

Answer 4

Have you tried to set a breakpoint within Test.aspx to see if the file is being executed at all? If it is, try setting Response.TrySkipIisCustomErrors to true within your Test.aspx file. If it isn't, your path might be wrong.

For responseMode="ExecuteURL", I've found path to be absolute to the root of whatever domain you've set up your application on, not relative to the application itself. Since the ASP.NET "relative tilde" ~/ is not allowed in path you need to set the full absolute path to the the .aspx file. If your application is found at http://localhost/MyApplication/ you need to set the following:

<error statusCode="404"
       subStatusCode="13"
       path="/MyApplication/FileUpload/Test.aspx"
       responseMode="ExecuteURL" />