It used to be the case where if you ran an on-premises Exchange 2007 or Exchange 2003 environment and you wanted to connect your organization to Office 365 then you were allowed a ‘free’ license of Exchange Server 2010 or Exchange Server 2013 for use in a hybrid deployment. This has now been extended regardless of what version you have on prem. Microsoft has now updated the wizard to issue keys for Exchange 2016 J To get a key go to



Conditions include:

“You can use the Hybrid Edition of Exchange Server 2016 only to enable hybrid functionality between Exchange Online users and on-premises Exchange 2010 or 2013 users. You cannot use the hybrid server to host on-premises mailboxes, to enable calendar sharing with other organizations (except for calendar sharing with Exchange Online users), to perform email filtering, or any other functionality that is not required for hybrid deployment.”