Exchange Server Standard 2013 (CU13) running on premises on Windows Server 2012 R2 (fully updated) on a 2012 R2 Active Directory Domain.
- External DNS is set correctly: autodiscover.mydomain.com successfully results from an external connection
- Wildcard SSL certificate is installed and functional
- I can access https://autodiscover.mydomain.com/autodiscover/autodiscover.xml from an external connection. I am prompted for username and password, which are accepted and I am then presented with a page showing Error 600 (expected result).
- AutoDiscover works and tests fine on the internal LAN.
However, I cannot get AutoDiscover to function over the Internet.
- I cannot get Outlook to connect via an external connection: not when using Outlook 2013 nor when using Outlook for Android or iOS. Outlook Web Access does work, but that is not relevant.
- https://testconnectivity.microsoft.com/ reports the following error:
Attempting to send an Autodiscover POST request to potential Autodiscover URLs. Autodiscover settings weren't obtained when the Autodiscover POST request was sent. Additional Details Test Steps The Microsoft Connectivity Analyzer is attempting to retrieve an XML Autodiscover response from URL https://autodiscover.mydomain.com:443/Autodiscover/Autodiscover.xml for user firstname.lastname@example.org. The Microsoft Connectivity Analyzer failed to obtain an Autodiscover XML response. Additional Details An HTTP 401 Unauthorized response was received from the remote Unknown server. This is usually the result of an incorrect username or password. If you are attempting to log onto an Office 365 service, ensure you are using your full User Principal Name (UPN). HTTP Response Headers: request-id: 03440b6d-56e0-405c-9f4e-eb663abca5b Set-Cookie: ClientId=AFD789F9E0A427AB; expires=Tue, 26-Sep-2017 12:53:11 GMT; path=/; HttpOnly Server: Microsoft-IIS/8.5 WWW-Authenticate: Basic realm="autodiscover.mydomain.com",Negotiate,NTLM X-Powered-By: ASP.NET X-FEServer: EXCHANGE-SERVER Date: Mon, 26 Sep 2016 12:53:11 GMT Content-Length: 0 Elapsed Time: 424 ms.
Per https://community.spiceworks.com/topic/550046-exchange-autodiscover-not-working-correctly-in-2010-2013-environment I have checked my bindings in IIS and see nothing amiss. Here they are:
Default Web Site: http Port:80 IP:*, net.pipe Binding:*, net.msmq Binding:localhost, msmq.formatname Binding:localhost, net.tcp Binding:808:*, https Port:443, http Port:80 IP:127.0.0.1, http Port:443 IP:127.0.0.1
Exchange Back End: http Port:81 IP:*, https Port:444 IP:*, net.pipe Binding:*
Per https://social.technet.microsoft.com/Forums/exchange/en-US/cc9ffe71-b4fe-4217-9343-14956ccf30d9/autodiscover-authentication?forum=exchangesvrgenerallegacy and http://www.itnotes.eu/?p=2455 I have checked authentication methods for the
/Autodiscoverapplication in IIS. Anyonymous, Basic, and Windows are enabled for
/Autodiscoverand Anonymous and Windows are enabled for the
Exchange Back End.
- I have checked that
Authenticated usershave permissions to the
/Autodiscoverapplications in IIS. For
Default Web Site,
Allow Readpermissions for
Authenticated Users. For
Exchange Back End,
Read & execute,
List folder contentsand
I'm really stuck here. I have no idea why this isn't working.