With both Exchange 2016 and 2019 going out of support in October 2025, we have heard from some of our customers that they have started their migrations to Exchange Subscription Edition (SE) but might...
Updated Jul 15, 2025
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We’re in the process of moving all user mailboxes to Exchange Online (included with Microsoft 365 Business Premium). As part of the required hybrid setup, we're following the supported upgrade path to Exchange Server Subscription Edition (SE).
Once all mailboxes are in the cloud, our intention is to use Exchange SE purely as a management server — to manage mail-related attributes for users via AD, keep things supported, and maintain hybrid connectivity.
Given this scenario:
All mailboxes will reside in Exchange Online
Exchange SE will be used for management purposes only
Do we still need to license Client Access Licences (CALs) for users, or is CAL licensing not required in this management-only configuration?