Set up custom 404 page in IIS 7 for HTML pages

http-status-code-404, iis-7

Solution

I too was having the same problem with `.htm` pages in IIS7 (not ASP, not .NET).

I changed `responseMode` to `File` instead of `ExecuteURL` in `<system.webServer>` and everything worked:

<httpErrors errorMode="Custom" existingResponse="Replace">
    <remove statusCode="404" />
    <error statusCode="404" responseMode="File" path="error.htm" />
</httpErrors>

Problem

I have my website in .htm extension and the server is IIS 7. I have now design custom 404 page. Now can anyone suggest me, how to implement custom 404 page by web.config.

Original source