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Released: 2025 H1 Cumulative Update for Exchange Server

The_Exchange_Team's avatar
The_Exchange_Team
Platinum Contributor
Feb 10, 2025
Today, we are announcing the availability of the 2025 H1 Cumulative Update (CU) for Exchange Server 2019 (aka CU15). This is the last CU we will release for Exchange Server 2019. CU15 includes new ...
Updated Feb 26, 2025
Version 9.0
administration
exchange 2019
on premises
setup
LiroBWI's avatar
LiroBWI
Copper Contributor
Feb 11, 2025

Look at the picture, is supported, but ONLY if you install NEW server with Exchange SE and move all ressources over to SE ..... as I understand this ....

niehweune's avatar
niehweune
Brass Contributor
Feb 11, 2025

Yes, that's how I understand the picture as well...

Point is that the previous posts about updating to SE (=link under Upgrade Paths in this post) always said we needed to do a legacy upgrade to 2019 CU15 first (so install new server with 2019 CU15 and move stuff), and then perform an in-place upgrade to SE (which is the first scenario in the picture).

  • Scott_Schnoll's avatar
    Scott_Schnoll
    Copper Contributor
    Feb 11, 2025

    That is a recommended upgrade path, not a required upgrade path.  We've been telling customers for years to move to Exchange 2019 so that they can do an in-place upgrade to Exchange SE.  But a legacy upgrade from Exchange 2016 is still supported and can be done, as well.

  • Nino_Bilic's avatar
    Nino_Bilic
    Icon for Microsoft rankMicrosoft
    Feb 11, 2025

    I have to admin to not understanding where the problem / confusion is. Essentially:

    • No in-place upgrade from Exchange 2016 to SE
    • If on E2016 and staying on-premises, one can do a legacy migration (add a new E2019 server to the organization and then move mailboxes to it from E2019)
    • When SE is released, that new E2019 server can be in-place upgraded to SE
    • Scott_Schnoll's avatar
      Scott_Schnoll
      Copper Contributor
      Feb 11, 2025

      Also, if on Exchange 2016 and staying on-prem, you can also do a legacy upgrade from Exchange 2016 to Exchange SE.

      • niehweune's avatar
        niehweune
        Brass Contributor
        Feb 12, 2025

        Scott_SchnollThanks for confirming.
        So in a nutshell, options to go from 2016 to SE are:
        - Migrate from 2016 to 2019 asap (= new server, legacy migration), followed by an in-place upgrade to SE (=basically the same as new CU install) when RTM is released (= what Nino_Bilic replied) - this is the recommended path.
        - Migrate from 2016 directly to SE (= new server, legacy migration) when RTM is released. Supported, but not recommended.

        Second option wasn't really clear from previous posts (the table only mentioned the first one) and frankly feels like a bad idea (with only 2 weeks tops between the release of SE RTM in Q4 & end-of-support for 2016/2019).

        TL;DR just keep pushing our customers to upgrade to 2019 now, like we've been doing for years😉