The enterprise-based email and calendar server program Microsoft Exchange Server 2019 is heading into a new stage of its lifecycle. Microsoft reminded us via a blog post that the program has reached the end of its mainstream support as of today, January 9, 2024.
While the mainstream support is officially ending today, Microsoft will still release new security updates for Exchange Server 2019 for a while longer. The Extended support for the program won"t end until October 14. 2025.
In addition, as Microsoft first revealed in November, Exchange Server 2019 will get two Cumulative Updates (CUs) in 2024. The first CU14, also known as H1 2024, will be released sometime later in January 2024.
Microsoft posted an explanation on why it will release new CUs for Exchange Server 2019 even as it has now reached its mainstream support end date:
Using Exchange 2019 as an example, the end of mainstream support is on January 9, 2024. That’s not the deadline for the release of CUs. January 9, 2024, is the last date you can request a bug fix or a Design Change Request (DCR) and have the Exchange team consider it. We will accept requests for bug fixes and DCRs until Jan 9. After that date, we will only consider security fixes. Anything filed on or before Jan 9 is fair game. And we might need some time to fix it.
The blog post stated that CU 14 will include new features like" TLS 1.3, an S/MIME control fix, Extended Protection on by default, and more." If you are a person who has a design change request or bug fix you want to put in, you have until the end of the day today to submit it.
The final feature update for Exchange Server 2019 will happen sometime later in 2024. It will be released as CU15 also known as H2 2024.