MC1462918 – M365 Change Digest

One-line summary

The September 2026 Windows security update will require a restart for all devices, including those enrolled in hotpatching, as some improvements cannot be updated without it.

Details

Summary

The September 2026 Windows security update requires a restart for hotpatch-enabled devices because it is a standard update. Devices will remain enrolled in hotpatching, with no changes to enrollment. Administrators should inform users, review restart policies, and monitor updates; no action or compliance changes are needed.

Body (from Message Center)

[What and why]

The September 2026 Windows security update will be released as a standard update rather than a hotpatch update. Some of the security improvements in this update change components that cannot be updated without a restart. As a result, devices enrolled in hotpatching will need to restart to complete installation.

[Rollout schedule]

September 2026: Standard update with restart required for all devices including those that are hotpatch-enabled.
October 2026: Planned baseline update month with restart required.
November 2026: Next hotpatch update expected.

[Impact on your organization]

Who is affected

Organizations using Windows Autopatch with hotpatch-enabled devices
Users of devices currently enrolled in hotpatch updates

Platforms and services

Windows Autopatch
Windows 11 hotpatch
Windows Server hotpatch

What will happen

Hotpatch-enabled devices will require a restart to complete installation of the September 2026 security update.
Hotpatch-enabled devices will remain enrolled in hotpatch updates.
Devices not using hotpatch updates are unaffected because standard Windows security updates already require a restart.
No changes are being made to hotpatch enrollment or configuration requirements.

[Action required / recommendations]

No action is required.

We recommend that administrators:

Inform affected users that a restart will be required following installation of the September 2026 security update.
Review maintenance windows and device restart policies to help ensure timely installation.
Continue monitoring update deployment and compliance through existing management tools.
Track the hotpatch update calendars on the Windows release health site for both Windows 11 and Windows Server.

Learn more

[Compliance considerations]

No compliance action is required. Update installation and restart behavior will be reflected in update history and compliance reports as usual.

Raw JSON (for debugging)

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    "details_map": {
      "Summary": "The September 2026 Windows security update requires a restart for hotpatch-enabled devices because it is a standard update. Devices will remain enrolled in hotpatching, with no changes to enrollment. Administrators should inform users, review restart policies, and monitor updates; no action or compliance changes are needed."
    },
    "id": "MC1462918",
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    "last_modified": "2026-08-27T22:06:04Z",
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  }
}