esu 2025

About this tag
The ESU 2025 tag on WindowsForum.com covers the end of support for Exchange Server 2016 and Exchange Server 2019 on October 14, 2025. Discussions focus on the urgent need to migrate to Exchange Online or the new Exchange Server Subscription Edition (SE) to avoid security risks and loss of updates. Topics include applying April 2025 hotfixes, preparing for hybrid enforcement windows, and understanding the implications of extended security updates (ESU) for on-premises Exchange environments. The tag is relevant for IT administrators and organizations planning their migration strategies before the deadline.
  1. End of Support for Exchange 2016/2019: Migrate to Online or SE Now

    On October 14, 2025, support for Exchange Server 2016 and Exchange Server 2019 ends — one month from now — and organizations that delay face escalating operational risk, loss of security updates, and an increasingly narrow set of safe upgrade paths. Microsoft’s Exchange engineering team has...