So you’re trying to set up the Exchange Autodiscovery but it just won’t work?

You’re checking your autodiscover URL http://exchange.contoso.com/autodiscover/autodiscover.xml but all you’re seeing it this stupid error message that tells you nothing, except:

<?xml version="1.0" encoding="utf-8" ?>  
<Autodiscover xmlns="http://schemas.microsoft.com/exchange/autodiscover/responseschema/2006">
  <Response>
    <Error Time="09:28:57.8739220" Id="2715916636">
      <ErrorCode>600</ErrorCode>
      <Message>Invalid Request</Message>
      <DebugData />
    </Error>
  </Response>
</Autodiscover>

If this is what’s happening to you, stop doing it :P You’ll never be able to check the autodiscover.xml from a browser. The contents of the file depend on the user agent of the client that requests it. Only Outlook (or compatible clients) will receive ANY configuration.

So, before you start deleting your virtual Autodiscover directory and re-create it it, make sure you’re using the correct client to verify your results.