1,456 questions
Solution: Add NETWORK SERVICE account to security for key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\AssistantsQuarantine root with full permissions
4.4.2 connection dropped due to socketerror
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Brian Taylor
15
Reputation points
Exchange 2016 2507.18 was just updated to Windows 2016 and now it is not delivery mail returning the following error in the Queue viewer:
[{LED 451 4.4.397 Error communicating with target host. -> 421 4.4.2 Connection dropped due to SocketError};{MSG=};{FQDN=spc-ex-04.domain.local;{IP=192.168.2.206};{LRT=<date>}]
What is causing this problem?
Thanks!
PS. I notice that event 7031, "The Microsoft Exchange Mailbox Transport Delivery service terminated unexpectedly." is occurring every 5 minutes
Exchange | Exchange Server | Other
2 answers
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Brian Taylor 15 Reputation points
2023-10-03T03:14:12.6166667+00:00 -
Brian Taylor 15 Reputation points
2023-10-03T20:14:59.2366667+00:00 Sorry, the Exchange server was updates from 2012R2 to 2016 causing the problem. The latest CU was installed but this did not fix the problem which ended up being a permissions issue on in the registry.
Yes, the event id was 25012: Exception System.UnauthorizedAccessException: Access to the registry key 'HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\AssistantsQuarantine\c9cce0f8-8fcd-4ae4-9d36-0f1297a9d58c\MSExchangeDelivery\PoisonControl\PoisonControlComposite' is denied.
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Kael Yao 37,746 Reputation points Moderator2023-10-03T02:45:23.9333333+00:00 Hi @Brian Taylor,
Exchange 2016 2507.18 was just updated to Windows 2016
Can you share some more information about the update?
Did you mean you installed a CU update for Exchange or you mean you installed a new Exchange server?
If you have multiple Exchange servers and this issue is with the newly installed one, please make sure this server is not in maintenance mode.
For more details: Event 7031 when you run Exchange maintenance scripts or Set-ServerComponentState
If this is not the case, are there other error or warning events in the event viewer?
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