I had this question after viewing Office 365 Hybrid Exchange - Mailbox provisioning
The link in this solution has expired.
I would like to:
Local AD: Create user and sync to Office 365 cloud.
Office 365: Apply appropriate license that includes Exchange email.
Problem and possible reasons: Account created but Exchange mailbox not provisioning. This used to be an old SBS server (upgraded to Win2K12 now). I think it still has old Exchange attributes, How do you rectify this?
If the user already existed, you will need to clear his Exchange attributes first, in particular the exchange mailbox GUID. Otherwise O365 will "think" the user has an on-premises mailbox and will not provision a new one even if you assign a license.
In any case, you should describe what you've done and what's the current setup in more detail.