Microsoft Windows Autopatch: September 2026 Windows security update requires a restart for hotpatch-enabled devices

[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

• Windows 11 hotpatch calendar - Windows 11 release information | Release health | Windows | Microsoft Learn
• Windows Server hotpatch calendar - Windows Server release information | Windows Search release information | Windows | Microsoft Learn

[Compliance considerations]

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