Microsoft has released Hotfix Updates (HUs) that address issues in earlier updates for:
Exchange Server 2019
Exchange Server 2016
HUs are available for the following specific versions of Ex...
Updated Jun 04, 2025
Version 3.0
Blog Post
Bhalchandra_Atre-MSFT
Microsoft
MicrosoftThis issue is fixed in August 2025 Windows Update
I'm currently trying to deploy a two-node DAG with Exchange Server SE + Windows Server 2025 Core. Servers are patched with updated July 2025 CU (KB5063666).
I can create the DAG with New-DatabaseAvailabilityGroup cmdlet. But as soon as I try to add a member inside the DAG with the Add-DatabaseAvailabilityGroupServer, I get the following error (after 15 minutes of processing) :
A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: An error occurred while attempting a cluster operation. Error: Cluster API failed: "CreateCluster() failed with 0x5b4. Error: This operation returned because the timeout period expired".
I've looked to all evidences (Exchange Trusted Subsystem is a member of the witness' server local admin groups, firewalls ports opened, trying to pre-stage the CNO object....), but whatever I try, I always end with the above error.
Do you know if this issue can be related with the fix you mention?
BTW, are you mentioning a Windows Server update (like a CU) or an Exchange hotfix?