Update October 16, 2026: For more information related to installation of October 2026 updates for Windows Server and the possible impact on Exchange Server, please see Exchange servers may become uns...
Updated Oct 16, 2026
Version 7.0
Blog Post
Mail Transfer stucked in Que after 24 Hours installing the KB. This Problem is on 3 Exhcange Servers SE
The Microsoft Exchange Mailbox Replication service was unable to process jobs in a mailbox database.
Error: MapiExceptionMdbOffline: Unable to make connection to the server. (hr=0x80004005, ec=1142)
Restart Solve this Problem.
Many Users have the same Problem. Look at Comment:
https://www.frankysweb.de/neue-sicherheitsupdates-fuer-exchange-server-oktober-2026/
New Post on Frankys Exchange Blog
https://www.frankysweb.de/exchange-server-se-probleme-mit-dem-oktober-update-kb5128895/
Hi.
Exactly same issue here after October Patch Tuesday: Windows Server 2019 and Exchange SE.
Reboot solved it for 20/22 hours.
We have the same problem here, mail queues up. Windows 2019 Server and Exchange SE. Problem started showing today. Patch was applied yesterday. We also had a problem to transfer active databases for the server we restarted when we put it into maintenance mode. Never experienced this problem before.
A note, we also applied the October Windows updates for Windows 2019 ServerHad to restart mailservers today 16/10 again approx 20-22 hours after last reboot.
What errors did you encounter with transferring active databases - here, require re-syncing and remounting with one DAG database failed too !
Unfortunately i didnt write down the error but it had something to do with mapiexeption or something like that. Maybe this "
mapiexceptionnetworkerror unable to make connection to the server"
We simply just tried restarting the server were the databases indicated failed status. And after reboot the started syncing by themself. So i guess this issue was on both servers. But we hadnt figured it out until we read about all this here.Today. I had to restart both DAG members again because of the issue but this time i could transfer the databases by the maintenance mode procedure. No error. But this time i noticed it in "time". Its seems that the longer you wait after the 22 hours the worse the symptomps get.
same problem here: OWA error, Mail stuck in queue.
Happend here too. Three server DAG. No access after around 24 hours. Reboot solved it. For now. Waiting for a test system to die, that was updated a view hours later.
MapiExceptionMdbOffline: Unable to make connection to the server. (hr=0x80004005, ec=1142) Diagnostic context: Lid: 41192 dwParam: 0x1 Lid: 55272 Lid: 34792 StoreEc: 0x6D8 Lid: 51176 StoreEc: 0x80040115 Lid: 48104 Lid: 39912 StoreEc: 0x80040115 Lid: 41192 dwParam: 0x2 Lid: 55272 Lid: 34792 StoreEc: 0x6D8 Lid: 51176 StoreEc: 0x80040115 Lid: 48104 Lid: 39912 StoreEc: 0x80040115 Lid: 41192 dwParam: 0x0 Lid: 49064 dwParam: 0x1 Lid: 38439 EMSMDBPOOL.EcPoolConnect called [length=194] Lid: 54823 EMSMDBPOOL.EcPoolConnect returned [ec=0x476][length=20][latency=0] Lid: 53361 StoreEc: 0x476 Lid: 51859 Lid: 33649 StoreEc: 0x476 Lid: 43315 Lid: 58225 StoreEc: 0x476 Lid: 39912 StoreEc: 0x476 Lid: 54129 StoreEc: 0x476 Lid: 50519 Lid: 59735 StoreEc: 0x476 Lid: 59199 Lid: 27356 StoreEc: 0x476 Lid: 65279 Lid: 52465 StoreEc: 0x476 Lid: 60065 Lid: 33777 StoreEc: 0x476 Lid: 59805 Lid: 52487 StoreEc: 0x476 Lid: 19778 Lid: 27970 StoreEc: 0x476 Lid: 17730 Lid: 25922 StoreEc: 0x476Our test system (Server 2025, Exchage SE, no DAG) now produces the same error after "only" 22 hours.
Any update by Microsoft on this issue and why it happened ?
Not jet. Maybe when the US wake up and find their servers not funktioning anymore.
