Microsoft has released Security Updates (SUs) for vulnerabilities found in:
Exchange Server Subscription Edition (SE)
Exchange Server 2019
Exchange Server 2016
SUs are available for the f...
Updated Sep 24, 2026
Version 4.0
Blog Post
Same issue persistent after Exchange Server SE RTM SU10 (KB5121608)
Released: August 2026 Exchange Server Security Updates | Microsoft Community Hub
Since exactly after installing Aug.26 Updates i have a ~ 2 Min Message Latency of nearly every Mail.
(Windows 2022 + CU KB5120242 + NET KB5121650; Exchange SE + SU9 KB5121573; German Localization Windows+Exchange)SMR 0,1
CAT → CATMS 15,0
QDM (Queue) 0,03
SDD → SDDR 120,2
These values (CATMS=15.001 / SDDR=120.216 ) are alway suspiciously round (15/120), so it looks like a timeout occurred in some component. Nothing logged in Eventviewer.
Furthermore, since the update, the search function no longer finds any new emails. It only finds emails that were received before i installed the Aug.26 update.
A very frustrating situation...
Btw:
This time, the installer complained about running processes (such as NLA and others). All applications running in the user context had been closed beforehand; only the installer was running.
I am also having search issues after the update. Certain emails won’t appear in the results, even though I can find them manually in the inbox. This is on the Outlook client and OWA.