I am using httpErrors
in my sites web.config to handle 404 errors. This was not working correctly until I added existingResponse="Replace"
to the node but now I dont get any yellow screen of death errors on my local development machine.
<httpErrors errorMode="Custom" existingResponse="Replace" >
<remove statusCode="404" subStatusCode="-1" />
<error statusCode="404" prefixLanguageFilePath="" path="/error.aspx?c=404" responseMode="ExecuteURL" />
</httpErrors>