Office 365/Exchange Online Setup
In order for Think 365 and Office 365 to work together, you will need to perform the following steps, in the order listed, in order to make sure that Lync Online will not interfere with Think 365.
NOTE: if you’re currently using Lync Online for any of your users, this step will impact their service. In this case, this step should only be performed as part of an overall migration of Lync to Think 365.
The attached Article covers…
• Set domain purpose
• Set user licenses
• Setup Exchange Online UM Dial Plan
• Enable UM mailboxes