September 8, 2026—KB5123099 (OS Build 14393.9512)

September 8, 2026—KB5123099 OS Build 14393.9512 Applies To Windows Server 2016, all editions Win 10 Ent LTSB 2016 Win 10 IoT Ent LTSB 2016 Important Free support for Windows 10 Enterprise 2016 LTSB and Windows Server 2016 will soon end. For information about the availability of Extended Security...

September 8, 2026—KB5124012 (OS Build 28000.2954)

September 8, 2026—KB5124012 OS Build 28000.2954 Applies To Windows 11 version 26H1, all editions This cumulative update for Windows 11, version 26H1 KB5124012 includes the latest security fixes and improvements, along with non-security updates from last month's optional preview release. Visit the...

KB5126934 - Description of the security update for SQL Server 2022 CU27: October 13, 2026

KB5126934 - Description of the security update for SQL Server 2022 CU27: October 13, 2026 Applies To SQL Server 2022 on Windows all editions SQL Server 2022 on Linux all editions Release date: October 13, 2026 Version: 16.0.4305.5 Summary Known issues in this update Improvements and fixes include...

October 13, 2026—KB5126653 (OS Build 22631.7652)

October 13, 2026—KB5126653 OS Build 22631.7652 Applies To Windows 11 version 23H2, all editions This cumulative update for Windows 11, version 23H2 KB5126653, includes the latest security fixes and improvements, along with non-security updates from last month’s optional preview release. Visit the...

October 13, 2026—KB5126651 (OS Build 17763.9376)

October 13, 2026—KB5126651 OS Build 17763.9376 Applies To Windows Server 2019 Win 10 Ent LTSC 2019 Summary This article lists the security issues and quality improvements included in this cumulative security update. Windows Server 2019 Windows 10, version 1809 Applies to: Windows Server 2019 This...

KB5128496 - Description of the security update for SQL Server 2017 CU31: October 13, 2026

KB5128496 - Description of the security update for SQL Server 2017 CU31: October 13, 2026 Applies To SQL Server 2017 on Linux SQL Server 2017 on Windows Release date: October 13, 2026 Version: 14.0.3560.2 Summary Known issues in this update Improvements and fixes included in this update How to...

KB5128492 - Description of the security update for SQL Server 2025 GDR: October 13, 2026

KB5128492 - Description of the security update for SQL Server 2025 GDR: October 13, 2026 Applies To SQL Server 2025 on Windows all editions, SQL Server 2025 on Linux all editions Release date: October 13, 2026 Version: 17.0.1145.4 Summary Known issues in this update Improvements and fixes include...

October 13, 2026-KB5127689 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 10 Version 21H2 and Windows 10 Version 22H2

October 13, 2026-KB5127689 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 10 Version 21H2 and Windows 10 Version 22H2 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 and 4.8.1 The October 13, 2026 update for Windows 10 Version 21H2 and Windows 10...

October 13, 2026-Security and Quality Rollup for .NET Framework 4.8 for Windows Server 2012 R2 (KB5127688)

October 13, 2026-Security and Quality Rollup for .NET Framework 4.8 for Windows Server 2012 R2 KB5127688 Applies To .NET Note Applies to: Microsoft .NET Framework 4.8 Important The installation of this Extended Security Update ESU might fail when you try to install it on an Azure Arc-enabled devi...

October 13, 2026-KB5127691 Cumulative Update for .NET Framework 4.8.1 for Windows 11, version 26H1

October 13, 2026-KB5127691 Cumulative Update for .NET Framework 4.8.1 for Windows 11, version 26H1 Applies To .NET Note Release date: October 13, 2026 Version: .NET Framework 4.8.1 The October 13, 2026 update for Windows 11, version 26H1 includes security and cumulative reliability improvements i...

October 13, 2026-KB5127690 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 24H2, Windows 11, version 25H2 and Microsoft server operating system 24H2

October 13, 2026-KB5127690 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 24H2, Windows 11, version 25H2 and Microsoft server operating system 24H2 Applies To .NET Note Release date: October 13, 2026 Version: .NET Framework 3.5 and 4.8.1 The October 13, 2026 update for...

October 13, 2026-KB5127696 Cumulative Update for .NET Framework 3.5 for Windows 11, version 26H1

October 13, 2026-KB5127696 Cumulative Update for .NET Framework 3.5 for Windows 11, version 26H1 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 The October 13, 2026 update for Windows 11, version 26H1 includes security and cumulative reliability improvements in .N...

KB5128494 - Description of the security update for SQL Server 2019 CU32: October 13, 2026

KB5128494 - Description of the security update for SQL Server 2019 CU32: October 13, 2026 Applies To SQL Server 2019 on Windows SQL Server 2019 on Linux Release date: October 13, 2026 Version: 15.0.4500.2 Summary Known issues in this update Improvements and fixes included in this update How to...

KB5128493 - Description of the security update for SQL Server 2022 GDR: October 13, 2026

KB5128493 - Description of the security update for SQL Server 2022 GDR: October 13, 2026 Applies To SQL Server 2022 on Windows all editions SQL Server 2022 on Linux all editions Release date: October 13, 2026 Version: 16.0.1210.3 Summary Known issues in this update Improvements and fixes included...

October 13, 2026—KB5126657 (OS Builds 19045.7807 and 19044.7807)

October 13, 2026—KB5126657 OS Builds 19045.7807 and 19044.7807 Applies To Windows 10 ESU Windows 10 Enterprise LTSC 2021 Windows 10 IoT Enterprise LTSC 2021 Important Free support for Windows 10 Enterprise LTSC 2021 ends on January 12, 2027. To learn about continuing support, see Plan for Windows...

October 13, 2026—KB5126836 (Monthly Rollup)

October 13, 2026—KB5126836 Monthly Rollup Applies To Windows Server 2012 R2 ESU Important Windows Server 2012 R2 reached the end of support on October 10, 2023. The Extended Security Updates ESU program for Windows Server 2012 R2 ended on October 13, 2026. This update is the final security update...

October 13, 2026—KB5126835 (Monthly Rollup)

October 13, 2026—KB5126835 Monthly Rollup Applies To Windows Server 2012 ESU Important End of support information: Windows Server 2012 reached the end of support on October 10, 2023. The Extended Security Updates ESU program for Windows Server 2012 ended on October 13, 2026. This update is the...

KB5127357: Servicing stack update for Windows Server 2012: October 13, 2026

KB5127357: Servicing stack update for Windows Server 2012: October 13, 2026 Applies To Windows Server 2012 ESU Summary This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates SSU makes sure that you have a robust...

KB5126967 - Description of the security update for SQL Server 2025 CU9: October 13, 2026

KB5126967 - Description of the security update for SQL Server 2025 CU9: October 13, 2026 Applies To SQL Server 2025 on Windows all editions, SQL Server 2025 on Linux all editions Release date: October 13, 2026 Version: 17.0.5015.4 Summary Known issues in this update Improvements and fixes include...

October 13, 2026-Security and Quality Rollup for .NET Framework 4.8 for Windows Server 2012 (KB5127686)

October 13, 2026-Security and Quality Rollup for .NET Framework 4.8 for Windows Server 2012 KB5127686 Applies To .NET Note Applies to: Microsoft .NET Framework 4.8 Important The installation of this Extended Security Update ESU might fail when you try to install it on an Azure Arc-enabled device...

KB5128495 - Description of the security update for SQL Server 2019 GDR: October 13, 2026

KB5128495 - Description of the security update for SQL Server 2019 GDR: October 13, 2026 Applies To SQL Server 2019 on Windows SQL Server 2019 on Linux Release date: October 13, 2026 Version: 15.0.2200.2 Summary Known issues in this update Improvements and fixes included in this update How to...

October 13, 2026-KB5127685 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10, version 1809 and Windows Server 2019

October 13, 2026-KB5127685 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10, version 1809 and Windows Server 2019 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 and 4.8 The October 13, 2026 update for Windows 10, version 1809 and Windows Server 2019...

October 13, 2026-KB5127683 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 Version 21H2 and Windows 10 Version 22H2

October 13, 2026-KB5127683 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 Version 21H2 and Windows 10 Version 22H2 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 and 4.8 The October 13, 2026 update for Windows 10 Version 21H2 and Windows 10 Versio...

October 13, 2026-KB5127666 Cumulative Update for .NET Framework 3.5 and 4.7.2 for Windows 10, version 1809 and Windows Server 2019

October 13, 2026-KB5127666 Cumulative Update for .NET Framework 3.5 and 4.7.2 for Windows 10, version 1809 and Windows Server 2019 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 and 4.7.2 The October 13, 2026 update for Windows 10, version 1809 and Windows Server...

October 13, 2026-Security and Quality Rollup for .NET Framework 3.5 for Windows Server 2012 R2 (KB5127664)

October 13, 2026-Security and Quality Rollup for .NET Framework 3.5 for Windows Server 2012 R2 KB5127664 Applies To .NET Note Applies to: Microsoft .NET Framework 3.5 Important The installation of this Extended Security Update ESU might fail when you try to install it on an Azure Arc-enabled devi...

October 13, 2026-Security and Quality Rollup for .NET Framework 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Server 2012 R2 (KB5127668)

October 13, 2026-Security and Quality Rollup for .NET Framework 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Server 2012 R2 KB5127668 Applies To .NET Note Applies to: Microsoft .NET Framework 4.6.2 Microsoft .NET Framework 4.7 Microsoft .NET Framework 4.7.1 Microsoft .NET Framework 4.7.2 Important The...

Description of the security update for Microsoft Exchange Server 2019 CU14 October 13, 2026 (KB5128897)

Description of the security update for Microsoft Exchange Server 2019 CU14 October 13, 2026 KB5128897 Applies To Exchange Server 2019 This security update resolves vulnerabilities in Microsoft Exchange Server. To learn more about these vulnerabilities, see the following Common Vulnerabilities and...

Description of the security update for Microsoft Exchange Server 2019 CU15 October 13, 2026 (KB5128896)

Description of the security update for Microsoft Exchange Server 2019 CU15 October 13, 2026 KB5128896 Applies To Exchange Server 2019 This security update resolves vulnerabilities in Microsoft Exchange Server. To learn more about these vulnerabilities, see the following Common Vulnerabilities and...

October 13, 2026-KB5127693 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows Server 2022

October 13, 2026-KB5127693 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows Server 2022 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 and 4.8.1 The October 13, 2026 update for Windows Server 2022 includes security and cumulative reliability...

October 13, 2026-KB5127692 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11 23H2

October 13, 2026-KB5127692 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11 23H2 Applies To .NET Note Release date: October 13, 2026 Version: .NET Framework 3.5 and 4.8.1 The October 13, 2026 update for Windows 11 23H2 includes security and cumulative reliability improvements in...

Description of the security update for Microsoft Exchange Server 2016 CU23 October 13, 2026 (KB5128898)

Description of the security update for Microsoft Exchange Server 2016 CU23 October 13, 2026 KB5128898 Applies To Exchange Server 2016 This security update resolves vulnerabilities in Microsoft Exchange Server. To learn more about these vulnerabilities, see the following Common Vulnerabilities and...

KB5128497 - Description of the security update for SQL Server 2017 GDR: October 13, 2026

KB5128497 - Description of the security update for SQL Server 2017 GDR: October 13, 2026 Applies To SQL Server 2017 on Windows SQL Server 2017 on Linux Release date: October 13, 2026 Version: 14.0.2140.2 Summary Known issues in this update Improvements and fixes included in this update How to...

October 13, 2026-Security and Quality Rollup for .NET Framework 3.5 for Windows Server 2012 (KB5127660)

October 13, 2026-Security and Quality Rollup for .NET Framework 3.5 for Windows Server 2012 KB5127660 Applies To .NET Note Applies to: Microsoft .NET Framework 3.5 Important The installation of this Extended Security Update ESU might fail when you try to install it on an Azure Arc-enabled device...

October 13, 2026—KB5127648 (OS Builds 26300.9711, 26200.9711 and 26100.9711)

October 13, 2026—KB5127648 OS Builds 26300.9711, 26200.9711 and 26100.9711 Applies To Windows 11 version 26H2, all editions Windows 11 version 25H2, all editions Windows 11 version 24H2, all editions Want a quick overview?: Watch the Windows 11 release note video for this update. --- Announcement...

October 13, 2026—KB5127646 (OS Build 28000.3231)

October 13, 2026—KB5127646 OS Build 28000.3231 Applies To Windows 11 version 26H1, all editions This cumulative update for Windows 11, version 26H1 KB5127646 includes the latest security fixes and improvements, along with non-security updates from last month's optional preview release. Visit the...

October 13, 2026-KB5127694 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11 26H2

October 13, 2026-KB5127694 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11 26H2 Applies To .NET Note Release date: October 13, 2026 Version: .NET Framework 3.5 and 4.8.1 The October 13, 2026 update for Windows 11 26H2 includes security and cumulative reliability improvements in...

October 13, 2026-KB5127684 Cumulative Update for .NET Framework 4.8 for Windows 10, version 1607 and Windows Server 2016

October 13, 2026-KB5127684 Cumulative Update for .NET Framework 4.8 for Windows 10, version 1607 and Windows Server 2016 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 4.8 The October 13, 2026 update for Windows 10, version 1607 and Windows Server 2016 includes securi...

October 13, 2026-KB5127687 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows Server 2022

October 13, 2026-KB5127687 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows Server 2022 Applies To .NET Note Release Date: October 13, 2026 Version: .NET Framework 3.5 and 4.8 The October 13, 2026 update for Windows Server 2022 includes security and cumulative reliability improvements...

October 13, 2026-Security and Quality Rollup for .NET Framework 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Server 2012 (KB5127667)

October 13, 2026-Security and Quality Rollup for .NET Framework 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Server 2012 KB5127667 Applies To .NET Note Applies to: Microsoft .NET Framework 4.6.2 Microsoft .NET Framework 4.7 Microsoft .NET Framework 4.7.1 Microsoft .NET Framework 4.7.2 Important The...

KB5126649: Servicing stack update for Windows 10, version 1607 and Windows Server 2016: October 13, 2026

KB5126649: Servicing stack update for Windows 10, version 1607 and Windows Server 2016: October 13, 2026 Applies To Win 10 Ent LTSB 2016 Win 10 IoT Ent LTSB 2016 Windows Server 2016, all editions Important Free support for Windows 10 Enterprise LTSB 2016 and Windows 10 IoT Enterprise 2016 LTSB en...

Add your Outlook.com account in classic Outlook for Windows

Add your Outlook.com account in classic Outlook for Windows Applies To Outlook for Microsoft 365 Outlook 2024 Outlook 2021 Outlook 2019 Outlook 2016 Outlook.com Get help with Copilot Can I add an Outlook.com account if I use two-factor? Can you explain my Account in Outlook.com? How can I add...

Description of the security update for Excel 2016: October 13, 2026 (KB5002934)

Description of the security update for Excel 2016: October 13, 2026 KB5002934 Applies To Excel 2016 Note This article originally described build 16.0.5574.1005. This release is now updated to build 16.0.5574.1006. The new build includes all security updates for Microsoft Excel 2016, and also fixe...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...

Microsoft Teams help & learning

Microsoft Teams help & learning Quick access Meetings Chat Notifications & settings Teams & channels Calls & devices Files Troubleshoot IT Pro & admin Get more done with Copilot in Teams Chat with Copilot in Teams Start a conversation with Copilot in Teams about files, chats, meetings, and more...