ASP.NET Custom 404 Returning 200 OK Instead of 404 Not Found

Question

After trying to setup my site for Google Webmaster Tools I found that my Custom ASP.NET 404 page was not returning the 404 status code. It displayed the correct custom page

Answer 1

The IIS 7 solution is to just add this to your web.config file:

<system.webServer>
  <httpErrors existingResponse="Replace">
    <remove statusCode="500" subStatusCode="-1" />
    <remove statusCode="404" subStatusCode="-1" />
    <error statusCode="404" prefixLanguageFilePath="" path="404.htm" responseMode="File" />
    <error statusCode="500" prefixLanguageFilePath="" path="500.htm" responseMode="File" />
  </httpErrors>
</system.webServer>

http://forums.asp.net/t/1563128.aspx/1