Web.config custom errors not working for 404's

Question

<customErrors mode="On" defaultRedirect="~/Error.aspx">
    <error statusCode="500" redirect="~/500/"/>
    <error statusCode="404" redirect="~/404/"/>
</customErrors>

This works fine for requests like:

~/egerg.aspx
~/wf92734eg.aspx

But for any other extension, this gives a server 404 page! How can I make the server 404 page redirect to my error page?

What IIS version are you running? – Daniel A. White Apr 08 '11 at 00:41 — Daniel A. White, Apr 08 '11 at 00:41
@Daniel IIS 7 on Windows 7 Ultimate – Tom Gullen Apr 08 '11 at 00:42 — Tom Gullen, Apr 08 '11 at 00:42

score 1 · Answer 1 · edited May 23 '17 at 12:05

This solution works on my website which is 99% webforms and 1% Razor/MVC 4 on .NET Framework 4.

In /Web.config:

<system.web>
  <customErrors mode="RemoteOnly" defaultRedirect="~/Error.aspx">
    <error statusCode="500" redirect="~/500/"/>
    <error statusCode="404" redirect="~/404/"/>
  </customErrors>
</system.web>

In the Page_Load event of your 404 handler (/404/default.aspx.cs, I assume):

protected void Page_Load(object sender, EventArgs e)
{
    Response.StatusCode = 404;
    Response.TrySkipIisCustomErrors = true;
}

Repeat the last step for the 500 handler.
The Application_Error method is empty in /Global.asax.cs.

This solution is very similar to this one.

Web.config custom errors not working for 404's

1 Answers1