We are migrating from on-premises Exchange 2010 to Office 365 for email domain @ourdomain.com.
In theory: When a mailbox moves, the TargetAddress attribute in ActiveDir is set to firstname.lastname@example.org. This redirects autodiscover to the new (Office 365) server. So when setting up a profile, Outlook goes to the on-prem server and from there redirects to Office 365:
- Outlook autodiscovers @ourdomain.com and ends up at the on-premises server
- TargetAddress attribute informs of new location @ourdomain.mail.onmicrosoft.com
- Outlook autodiscovers @ourdomain.mail.onmicrosoft.com and ends up at Office 365
- Mailbox is found and Outlook is configured
In practice: We cannot setup Outlook. Instead we receive a pop up "The action cannot be completed"
The problem is that we are using local autodiscover XML file for @ourdomain.com. If I remove the local XML, everything works fine. However I thought that the local file will only affect the first step of the process. How come subsequent steps also get thrown off? Anything ideas how to remedy this?