Connecting Outlook 2013 to Office 365 2013 Wave 15

We recently completed a migration to Office 365 2013 from exchange and were forced migrate faster than anticipated. Our staff primarily uses Outlook and during the migration were forced to use Outlook where existing mail was and the web version of OWA. To put it mildly, our users were unhappy with this arrangement.

The way Outlook wants to find Office365 is through the autodiscover. Unfortunately, on a local network, you need to finalize the migration process after all mail has been moved to change the AD attributes that allow users to simply find autodiscover.

The intermediate method would be to setup a manual server mapping which used to just involve looking up your office365 server. To do this you now need the users unique Exchange GUID.

The following are the steps to obtain that GUID and setup a manual outlook to Office365 mapping. This will be useful during the migration process or when testing, but you should setup a profile using autodiscover for long term.

To get the exchange GUID for the user, run powershell as an admin and run the following commands using your Office 365 credentials


PS C:\windows\system32> Set-ExecutionPolicy Unrestricted

PS C:\windows\system32> $livecred = Get-Credential

PS C:\windows\system32> $session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook
.com/powershell/ -Credential $livecred -Authentication basic -allowredirection

PS C:\windows\system32> Import-PSSession $session

PS C:\windows\system32> Get-Mailbox -Identity username@domain.com | select ExchangeGUID

ExchangeGuid
------------
28f66595-de7c-40cb-93cc-5553bb990549

This exchange GUID is the number you need.

You will then want to open up the mail settings in the Control Panel to create a new profile.

Add a new Microsoft Exchange account and user the following format to create your server name.

https://outlook.office365.com/mapi/emsmdb/?MailboxId=28f66595-de7c-40cb-93cc-5553bb990549@domain.com

The key is the mailbox ID is your ExchangeGUID@domain.com.

Hopefully that helps during your email migration to the cloud.