Over the last several weeks we have received several questions about possible extension of the Exchange Server 2016/2019 ESU program past October 2026. After all, in our original Exchange 2016/2019 E...
Updated Aug 14, 2026
Version 3.0
Blog Post
Hi guys,
Thank you for sharing, but I have a question. Will the mixed deployment of these versions be affected after ESU ends?
- Nino_Bilic
Microsoft
After ESU ends (and no more updates are available for Exchange 2016/2019 to any customers) - the expectation should be that any Exchange 2016/2019 servers will be stay out of date and as time goes on, will become more and more outdated as time goes on. This might manifest itself in not just vulnerabilities of those servers, but also possibly things that do not work properly between Exchange SE servers (which will still receive updates as supported product) and Exchange 2016/2019 servers that will be out of date.
I might not have fully understood your question, please clarify if the above does not cover it.
