Why set subStatusCode to -1 in Web.config?

Apologies if this is obvious, but I have searched around and am unable to find an answer.

In a .net Web.config file, could anyone tell me what setting the subStatusCode to - 1 does?

<httpErrors errorMode="Custom" existingResponse="Replace">
      <clear />
      <remove statusCode="404" subStatusCode="-1" />
      <error statusCode="404" prefixLanguageFilePath="" path="/Error.aspx" responseMode="ExecuteURL" />
</httpErrors>

My guess is that it means all the 'sub' codes, 404.1, 404.2.. etc?

Why set subStatusCode to -1 in Web.config?

1 Answers