Exchange Transport Rules and Data Loss Prevention rules don't work after installing November 2024 SU V1

Symptoms

After you install the Microsoft Exchange Server 2019 or 2016 November 2024 security update (SU) Version 1, Exchange Server stops processing Exchange Transport Rules (ETR) and Data Loss Prevention (DLP) rules. In some cases, rules might be processed for a few hours before the process stops working. After you restart the MSExchangeTransport service, rules begin to process but stop again. Although the symptoms occur, you see no evidence of the issue, such as event log entries.

Resolution

To fix this issue, install the following security update:

• Description of version 2 of the security update for Microsoft Exchange Server 2019 and 2016: November 27, 2024 (KB5049233)