| 解決 | Incorrect notifications that "Microsoft Defender Antivirus is turned off" Microsoft Defender Antivirus remains active and functioning correctly despite notifications following the latest update. 解決日: 2026-09-30(配布元の記載)詳細- Affected platforms
- Client: Windows 11, version 26H1; Windows 11, version 25H2; Windows 11, version 24H2; Windows 11, version 23H2; Windows 10, version 22H2; Windows 10, version 21H2; Windows 10 Enterprise LTSC 2019; Windows 10 Enterprise LTSC 2016 Server: Windows Server 2025; Windows Server 2022; Windows Server 2019; Windows Server 2016; Windows Server 2012 R2; Windows Server 2012
| 2026-09-30 |
| 回避策あり | USB audio devices might fail to start or produce no sound Some USB Audio Class 1.0 devices display Code 10 or fail in multichannel audio modes after installing the Sept. 8 update きっかけ: OS Build 22621.7582 KB5122880 2026-09-08詳細- Affected platforms
- Client: Windows 11, version 26H2; Windows 11, version 26H1; Windows 11, version 25H2; Windows 11, version 24H2; Windows 11, version 23H2; Windows 10, version 22H2; Windows 10, version 21H2; Windows 10 Enterprise LTSC 2019; Windows 10 Enterprise LTSC 2016 Server: Windows Server 2025; Windows Server 2022; Windows Server 2019; Windows Server 2016; Windows Server 2012 R2; Windows Server 2012
| 2026-09-29 |
| 解決 掲載終了 | Remote Desktop Services might stop responding after Sept. 2026 security update Some Windows devices with Remote Desktop enabled might experience Remote Desktop Services (RDS) instability. きっかけ: OS Build 22621.7582 KB5122880 2026-09-08 解決日: 2026-09-14(配布元の記載)詳細- Resolution
- KB5129242
- Affected platforms
- Client: Windows 11, version 26H1; Windows 11, version 25H2; Windows 11, version 24H2; Windows 11, version 23H2; Windows 10, version 22H2; Windows 10, version 21H2; Windows 10 Enterprise LTSC 2019; Windows 10 Enterprise LTSC 2016 Server: Windows Server 2025; Windows Server 2022; Windows Server 2019; Windows Server 2016; Windows Server 2012 R2; Windows Server 2012
| 2026-09-17 |
| 解決 掲載終了 | Host folder shares might be unavailable in Hyper-V-based Linux VMs Plan9 host folder shares might not appear in the guest environment after installing the September 2026 security update. きっかけ: OS Build 22621.7582 KB5122880 2026-09-08 解決日: 2026-09-14(配布元の記載)詳細- Resolution
- KB5129242
- Affected platforms
- Client: Windows 11, version 26H1; Windows 11, version 25H2; Windows 11, version 24H2; Windows 11, version 23H2; Windows 10, version 22H2; Windows 10, version 21H2 Server: None Click here to manage email notifications for Windows known issues.
| 2026-09-14 |