Exchange 2010 Autodiscover Failure

After doing a network trace and looking at the IIS logs, I've discovered:

   . the client has established a session with the Exchange server and has sent two packets:
            . normal web Post packet
            . an xml request for autodiscover.xml
   . the server responds with an ACK but then all communications stop and the client restarts the process thus that's why it's reporting timeout

The IIS log is showing three GET attempts against Autodiscover.xml.  The first two have no username and the result is an error return code of 401.1.  The last log entry shows my credentials being passed and the status return code is 200 (OK).  So I'm confused as to why the server's not responding having authenticated me.  Interestingly, there are three authentication methods: anonymous, Basic and Windows Integrated.

i wrote two articles on this topic. the first one discusses how autodiscover works and the second is for troubleshooting

https://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/A_3585-Exchange-Autodiscover-and-Web-Services-OOF-and-OAB.html

https://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/A_3704-Troubleshooting-Outlook-Certificate-Errors.html

post any questions or errors you have after working thru the second article

Thank you so much for taking the time to assist!!!

I gathered the information you spoke of in the posting and it is displayed below.  But first:

     . there is only one site with one Exchange 2003 server and one Exchange 2010 server
     . we're a small non-profit with only 1 external IP address; port 443 is in use on the Exchange 2003 server thus I chose to use a different port for Exchange 2010 OWA (50100)
     . all SMTP traffic passes through the Exchange 2003 server; that's working perfectly
     . OAB to Exchange 2010 works
     . external DNS name = internal DNS name
     . self signed, single SAN cert
     . not using Outlook anywhere (yet)  at this point, just interested in getting OAB, OOF and free/busy to work

Also, looking deeper in the IIS log (on the Exchange 2010 server), I see that three attempts to access autodiscover.xml were issued (presumably by Exchange). The first two have no user name given and they show a failure of 401.   However, the third shows my user name and a return status of 200 (which as you know for web functions, that's successful).  Interestingly, I have 3 authentications enabled: Anonymous, Basic and Windows Integrated.  I suspect Exchange is pursuing authentication in that order and finally I'm authenticated via Windows Integrated.  However a sniffer trace done while the TestEmailAutoConfiguration runs shows the xml being sent and Exchange 2010 ACKnowledging it but then no further traffic and thus the timeout.

Perhaps you can't change the port for 443 traffic???????

Here's the info from the displays:

[PS] C:\Windows\system32>get-exchangecertificate | where { $_.Services.ToString().Contains("IIS") -eq $true} | fl Cert*


CertificateDomains : {Exchange2, Exchange2.achieve-ability.org}
CertificateRequest :



[PS] C:\Windows\system32>get-clientaccessserver | fl


RunspaceId                           : 4895292b-e100-496c-b0ef-9a3500bfa945
Name                                 : EXCHANGE2
Fqdn                                 : EXCHANGE2.achieve-ability.org
OutlookAnywhereEnabled               : True
AutoDiscoverServiceCN                : Exchange2
AutoDiscoverServiceClassName         : ms-Exchange-AutoDiscover-Service
AutoDiscoverServiceInternalUri       : https://exchange2:50100/Autodiscover/Autodiscover.xml
AutoDiscoverServiceGuid              : 77378f46-2c66-4aa9-a6a6-3e7a48b19596
AutoDiscoverSiteScope                : {Default-First-Site-Name}
AlternateServiceAccountConfiguration :
IsValid                              : True
ExchangeVersion                      : 0.1 (8.0.535.0)
DistinguishedName                    : CN=EXCHANGE2,CN=Servers,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Ad
                                       ministrative Groups,CN=Achieve-Ability,CN=Microsoft Exchange,CN=Services,CN=Conf
                                       iguration,DC=achieve-ability,DC=org
Identity                             : EXCHANGE2
Guid                                 : 3ed6b8d0-bd76-467c-b1c4-a3fd45f1e2fe
ObjectCategory                       : achieve-ability.org/Configuration/Schema/ms-Exch-Exchange-Server
ObjectClass                          : {top, server, msExchExchangeServer}
WhenChanged                          : 10/4/2010 12:58:00 PM
WhenCreated                          : 10/2/2010 11:46:10 AM
WhenChangedUTC                       : 10/4/2010 4:58:00 PM
WhenCreatedUTC                       : 10/2/2010 3:46:10 PM
OrganizationId                       :
OriginatingServer                    : nemo.achieve-ability.org



[PS] C:\Windows\system32>get-webservicesvirtualdirectory | Fl *Url


InternalNLBBypassUrl : https://exchange2.achieve-ability.org:50100/ews/exchange.asmx
InternalUrl          : https://exchange2.achieve-ability.org:50100/EWS/Exchange.asmx
ExternalUrl          : https://www1.achieve-ability.org:50100/EWS/Exchange.asmx


[PS] C:\Windows\system32>get-oabvirtualdirectory | fl *Url


InternalUrl : http://exchange2.achieve-ability.org/OAB
ExternalUrl : https://mail.achieve-ability.org/OAB


[PS] C:\Windows\system32>get-autodiscovervirtualdirectory | fl *Url


InternalUrl :
ExternalUrl :


[PS] C:\Windows\system32>get-outlookanywhere | fl External*


ExternalHostname : anywhere.achieve-ability.org

As a final test, I simply changed the port back to the standard port of 443 and the autodiscover function worked.  And as expected, when it was changed back to 50100, it failed.  Conclusion seems to be that Exchange is not equipped to handle a port other than 443.

yes, outlook is coded to attempt https://domain.com/autodiscover/autodiscover.xml and if that fails https://autodiscover.domain.com/autodiscover/autodiscover.xml

it will not attempt another port

After looking at additional postings, I've come to the realization that trying to run off of different ports doesn't work.  That is, I can get OWA working externally on a different port but getting autodiscover to work using different ports is not supported.  Perhaps it can be done, as one post suggests, through the use of multiple web sites but I'm not willing to go there.  As you stated, and as I plan to do, I'll do a full-scale migration to the new server and restore the default ports when that happens.  I'm sure that life will return to normal once that is done.  

Thanks for your efforts to help me try and solve this!