I have a multi-tennat Exchange environment. I am trying to migration from 2007 to 2013 and all but one customer is working fine.
When I try to setup Outlook on this one customer's computers (in their office), Outlook says, "The action cannot be completed. The name cannot be matched to a name in the address list." When I click OK, Outlook shows me the user's mailbox server in the Micorsoft Exchange server field (the Exchange 2007 server).
I verified that the customer has an Autodiscover SRV record in internal and external DNS, and that the test user can log into webmail internally. I also verified that I can telnet to the 2013 CAS's external IP address over 443. Finally, I verified that webmail.hostedDomain.com resolves to the correct IP (and responds to ping).
When I try to setup the same account on a laptop outside of the customer's network (specifically, the same domain as the Exchange servers), Autodiscover works fine and I can log into the mailbox.
From the test machine (on the customer's network), Remote Connectivity Analyzer shows:
Attempting to send an Autodiscover POST request to potential Autodiscover URLs. Autodiscover settings weren't obtained when the Autodiscover POST request was sent.
The Microsoft Connectivity Analyzer is attempting to retrieve an XML Autodiscover response from URL https://webmail.hostedDomain.com:443/Autodiscover/Autodiscover.xml for user dtest@customerDomain.com. The Microsoft Connectivity Analyzer failed to obtain an Autodiscover XML response.
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: 6a387132-e372-4bf9-9833-779286820a61 Set-Cookie: ClientId=HMCLPHFOUYPIWAYOVXSW; expires=Fri, 05-Aug-2016 16:57:49 GMT; path=/; > HttpOnly Server: Microsoft-IIS/8.5 WWW-Authenticate: Negotiate,NTLM,Basic realm="webmail.hostedDomain.com" X-Powered-By: ASP.NET X-FEServer: E2013ServerName Date: Thu, 06 Aug 2015 16:57:49 GMT Content-Length: 0