Resources: · Learn about the different types of monthly updates: msft.it/6017eRKoX · Find resources, tools, and news about known issues and safeguards: msft.it/6016eRKon · Have an issue? File feedback to our engineers: msft.it/6018eRKok (🧵7/7)

IMPORTANT: Secure Boot certificates used by most Windows devices started to expire on June 2026. This might affect the ability of certain personal and business devices to boot securely if not updated in time. To avoid disruption, we recommend reviewing the guidance and taking action to update certificates in advance. Learn more by visiting the Secure Boot playbook. techcommunity.microsoft.com/… (🧵6/7)

Watch our short monthly release notes video for a summary of this month’s Windows 11 update. aka.ms/Windows11/ReleaseNote… (🧵5/7)

This security update includes improvements that were a part of KB5120998 (released August 27, 2026) nitter.net/WindowsUpdate/status/2… (🧵4/7)

Highlights for Windows 11, version 25H2: ➡️ The update includes security fixes that are documented in the Security Update Guide. msrc.microsoft.com/update-gu… ➡️ This update expands high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. Devices receive the new certificates only after demonstrating sufficient successful update signals, maintaining a controlled and phased rollout. ➡️ This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. (🧵3/7)

Windows 11 release notes: · Version 26H1 (KB5124012): support.microsoft.com/help/5… · Version 24H2 & 25H2 (KB5124008): support.microsoft.com/help/5… · Version 23H2 (KB5122880): support.microsoft.com/help/5… (🧵2/7)

The September 2026 Windows security updates are now available for Windows 11. (🧵1/7)

Resources: · Learn about the different types of monthly updates: msft.it/6017eRKoX · Find resources, tools, and news about known issues and safeguards: msft.it/6016eRKon · Have an issue? File feedback to our engineers: msft.it/6018eRKok (🧵7/7)

IMPORTANT: Secure Boot certificates used by most Windows devices are started to expire on June 2026. This might affect the ability of certain personal and business devices to boot securely if not updated in time. To avoid disruption, we recommend reviewing the guidance and taking action to update certificates in advance. Learn more by visiting the Secure Boot playbook. techcommunity.microsoft.com/… (🧵6/7)

Watch our short monthly release notes video for a summary of this month’s Windows 11 update. aka.ms/Windows11/ReleaseNote… (🧵5/7)

This security update includes improvements that were a part of KB5101684 (released July 28, 2026) nitter.net/WindowsUpdate/status/2… (🧵4/7)

Highlights for Windows 11, version 25H2: ➡️ The update includes security fixes that are documented in the Security Update Guide. msrc.microsoft.com/update-gu… ➡️ This update expands high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. Devices receive the new certificates only after demonstrating sufficient successful update signals, maintaining a controlled and phased rollout. ➡️ This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. (🧵3/7)

Windows 11 release notes: · Version 26H1 (KB5121000): support.microsoft.com/help/5… · Version 24H2 & 25H2 (KB5121003): support.microsoft.com/help/5… · Version 23H2 (KB5120240): support.microsoft.com/help/5… (🧵2/7)

The August 2026 Windows security updates are now available for Windows 11 (🧵1/7)

Have questions about how device manufacturers support Secure Boot certificate updates? OEM Secure Boot Office Hours are open today - July 15 - until 7:00 PM PDT. Visit aka.ms/OfficeHours/SecureBoo… to post your questions for our OEM partners.

Resources: Learn about the different types of monthly updates: msft.it/6017eRKoX Find status and known issues for each release: msft.it/6016eRKon Have an issue? File feedback to our engineers: msft.it/6018eRKok (🧵5/5)

Release note video Check out this month's release note video with a special tip on how to use Phone Link. aka.ms/Windows11/ReleaseNote… (🧵4/5)