It can be a bit difficult to configuring an Outlook profile for Office 365 wave 15 or Exchange 2013, if the autodiscover points to your on-premise Exchange environment or the old Exchange environment, since the Outlook clients now connect to ExchangeGUID@domain.com and not by RPC to the Client Access server, as is Exchange 2010.
So in order to configure your Outlook profile, you must know (look up) the ExchangeGUID, primary SMTP address and UPN. This can be done by using PowerShell against Exchange Online (or Exchange 2013). You’ll find the information, if you run this command:
Get-Mailbox USERNAME | fl Name, ExchangeGUID, PrimarySMTPAddress, UserPrincipalName
Now that you have the necessary user information, you can go ahead and configure an Outlook profile manually:
Open Outlook and select “Manual setup or additional server types” -> “Next”
Enter your “Exchange GUID”@YOURDOMAIN.COM in the Server field and your “UPN” in the User Name field
Click “More Settings” and choose the “Security” tab
Remove the checkmark from “Encrypt data between Microsoft Outlook and Microsoft Exchange” and select “Anonymous Authentication” in “Logon network security”
Go to the “Connection” tab and put a checkmark in “Connect to Microsoft Exchange using HTTP”
For Office 365 accounts:
Click at the “Microsoft Exchange Proxy Settings…” button, and enter “outlook.office365.com” in the “Use this URL to connect to my proxy server for Exchange” field, put a checkmark in “Only connect to proxy servers that have this principal name in their certificate” and enter “msstd:outlook.com”, put a checkmark in “On fast networks, connect using HTTP first, then connect using TCP/IP” and set proxy authentication to “Basic Authentication”.
For Exchange 2013 accounts:
Click at the “Microsoft Exchange Proxy Settings…” button, and enter your webmail url in the “Use this URL to connect to my proxy server for Exchange” field, put a checkmark in “On fast networks, connect using HTTP first, then connect using TCP/IP” and set proxy authentication to “Basic Authentication”.
Click “OK” -> “OK” to get back to the “Server settings” page and then click “Check name”.
Enter the UPN and password of the user.
The names will be resolved and your Outlook profile is now configured with success.