Microsoft Re-Releases the November 2024 Exchange Server Security Updates
Published: Nov 29, 2024
This week, Microsoft re-released the November 2024 Exchange Server security updates, now known as November 2024 SUv2. The first release didn’t go so well. The original updates, which went out on November 12, 2024, caused issues with data loss prevention (DLP) rules and transport rules, leading to disruptions in on-premises email flow.
You can find the downloads for the updated release in Microsoft’s original blog post here.
Microsoft offered a relatively simple table to help Exchange Server administrators choose the correct path based on their current environment and actions.
| If Nov 2024 SUv1… | Then… |
| was installed manually and you do not use any transport or DLP rules, | it is recommended to install the Nov 2024 SUv2 to gain more granular control over the X-MS-Exchange-P2FromRegexMatch header. Please see the FAQ below. |
| was installed using Microsoft / Windows update and you do not use any transport or DLP rules, | in December 2024, the server will download and install the Nov 2024 SUv2. |
| was installed (manually or automatically) and then uninstalled to fix the issue with transport rules, | install the re-released Nov 2024 SUv2. |
| was never installed, | install the re-released Nov 2024 SUv2. |
In case it’s unclear, if you’ve installed the original ‘Nov 2024 SUv1’ updates and have experienced no issues, you are still recommended to install the new Nov 2024 SUv2 update.
The new package resolves the issue with transport rules introduced in the first update and offers more granular control for “non-RFC compliant P2 FROM header detection.”
As a reminder, the only on-premises Exchange Server versions that remain supported are Exchange Server 2016 CU23 and Exchange Server 2019 CU13 and CU14. Both of these versions go out of support on October 14, 2025. You may as well be doing some “pre-production” planning for the next version – starting in the third quarter of 2025, Microsoft Exchange Server Subscription Edition (SE) will be released. You’ll be able to upgrade from Exchange Server 2016 CU23 and Exchange Server 2019 CU15 (coming soon).