Win Update KB5129195 Windows 11 Out-of-band Cumulative Update build 26100.9457 (24H2), 26200.9457 (25H2), and 26300.9457 (26H2) - Sept. 14



 Microsoft Support:

This out-of-band (OOB) update for Windows 11, version 25H2 and Windows 11, version 24H2 (KB5129195) is cumulative. It includes updates from previous releases, along with additional security and non-security improvements. Visit the Windows release health dashboard for the latest status on this release.

Improvements​

This OOB update includes the following improvement:
  • [Security] This update includes protections documented in CVE-2026-62721, which refers to a Windows User-Mode Power Service (UMPS) Elevation of Privilege vulnerability.
  • [Remote Desktop Services (known issue)] Fixed: This update addresses an issue affecting Remote Desktop Services (RDS) after installing the September 2026 Windows security update (KB5122880). In affected environments, RDS might become unstable, causing RDP connection and sign-in failures or servers to become unresponsive during Remote Desktop configuration. Related tools, including Microsoft Management Console (MMC), RDS Licensing Diagnoser, File Explorer, and the Windows Update page, might also stop responding.
  • [Hyper-V (known issue)] Fixed: Some applications that use HCS-managed virtual machines experienced issues when sharing host folder with Linux VMs using Plan9. Folders shared from the Windows host using Plan9 did not appear or could not be accessed in the guest environment.
  • [8-channel or 3D audio modes] Fixed: Some USB Audio Class 1.0 devices functioning as expected in standard stereo configurations failed when using multichannel audio features, including 8-channel or 3D audio modes. (Note: There are other audio symptoms not resolved in this OOB update. See the “Known issues in this update” section for more information.)

Component updates​

Windows 11 servicing stack update (KB5124007) - 22621.9441​

This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates (SSU) ensure that you have a robust and reliable servicing stack so that your devices can receive and install Microsoft updates. To learn more about SSUs, see Simplifying on-premises deployment of servicing stack updates.

Known issues in this update​

Symptoms

After installing the September 8, 2026, Windows security update, some USB Audio Class 1.0 devices might fail to start or produce audio. Affected devices might experience one or more of the following symptoms: The device displays an error in Device Manager: "This device cannot start (Code 10).” No audio output. Volume controls are unresponsive or remain at zero. Sound settings are unresponsive or unavailable. This issue is limited to USB Audio Class 1.0 devices.

Resolution
Microsoft is working on a resolution and will update this documentation when more information is available.

How to get this update​

Before you install this update

Microsoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

Install this update

To install this update, use one of the following Windows and Microsoft release channels.

Available​
Next Step​
Available
This update downloads and installs automatically from Windows Update and Microsoft Update.
Available
To install this update, download the standalone package(s) for this update from the Microsoft Update Catalog. This update contains MSU files that require installation in a specific order. Follow the Arm64 installation instructions or x64 installation instructions, as appropriate.

If you install additional Dynamic Update packages, use versions from the same release month as this update. If a Safe OS Dynamic Update or Setup Dynamic Update is not available for the same release month, use the most recently released version.

Note This latest cumulative update includes updates for AI components. AI components are applicable only to Copilot+ PCs and will not install on other Windows client PCs or Windows Server.

File Information

For a list of the files provided in this update, download the file information for cumulative update KB5129195.

For a list of the files provided in the servicing stack update, download the file information for SSU KB5124007 - versions 22621.9441.


 Source:

September 14, 2026—KB5129195 (OS Builds 26200.9457 and 26100.9457) Out-of-band | Microsoft Support

September 14, 2026—KB5129195 (OS Builds 26200.9457 and 26100.9457) Out-of-band
support.microsoft.com support.microsoft.com


Check Windows Updates


ISO from Microsoft MCT:

www.elevenforum.com

Download Official Windows 11 ISO file from Microsoft

This tutorial will show you how to download an official Windows Server or Windows 11 64-bit or ARM64 ISO file from Microsoft. Microsoft provides ISO files for Windows Server and Windows 11 to download. You can use these ISO files to clean install or in-place upgrade Windows 11. The Flight Hub...
www.elevenforum.com www.elevenforum.com


UUP Dump:

64-bit ISO download:
uupdump.net

Select language for Windows 11, version 24H2 (26100.9457) amd64

Select language for Windows 11, version 24H2 (26100.9457) amd64 on UUP dump. UUP dump lets you download Unified Update Platform files, like Windows Insider updates, directly from Windows Update.
uupdump.net
uupdump.net

Select language for Windows 11, version 25H2 (26200.9457) amd64

Select language for Windows 11, version 25H2 (26200.9457) amd64 on UUP dump. UUP dump lets you download Unified Update Platform files, like Windows Insider updates, directly from Windows Update.
uupdump.net
uupdump.net

Select language for Windows 11, version 26H2 (26300.9457) amd64

Select language for Windows 11, version 26H2 (26300.9457) amd64 on UUP dump. UUP dump lets you download Unified Update Platform files, like Windows Insider updates, directly from Windows Update.
uupdump.net

ARM64 ISO download:
uupdump.net

Select language for Windows 11, version 24H2 (26100.9457) arm64

Select language for Windows 11, version 24H2 (26100.9457) arm64 on UUP dump. UUP dump lets you download Unified Update Platform files, like Windows Insider updates, directly from Windows Update.
uupdump.net
uupdump.net

Select language for Windows 11, version 25H2 (26200.9457) arm64

Select language for Windows 11, version 25H2 (26200.9457) arm64 on UUP dump. UUP dump lets you download Unified Update Platform files, like Windows Insider updates, directly from Windows Update.
uupdump.net
uupdump.net

Select language for Windows 11, version 26H2 (26300.9457) arm64

Select language for Windows 11, version 26H2 (26300.9457) arm64 on UUP dump. UUP dump lets you download Unified Update Platform files, like Windows Insider updates, directly from Windows Update.
uupdump.net

www.elevenforum.com

UUP Dump - Download Windows Insider ISO

UUP Dump is the most practical and easy way to get ISO images of any Insider Windows 10 or Windows 11 version, as soon as Microsoft has released a new build. UUP Dump creates a download configuration file according to your choices, downloads necessary files directly from Microsoft servers, and...
www.elevenforum.com www.elevenforum.com
 
Last edited:
Click to expand...
Downloading and installing.

1789416786361.webp

1789416916800.webp


Done:

Edition Windows 11 Pro
Version 25H2
Installed on ‎6/‎9/‎2026
OS build 26200.9457
Experience Windows Feature Experience Pack 1000.26100.360.0

Edit:
Updated 3 machines on Public Build.
 
Last edited:

My Computer My Computer

At a glance

Windows 11 Pro 25H2Intel I9-9900K64GBNVIDIA RTX 2060
OS
Windows 11 Pro 25H2
Computer type
PC/Desktop
Manufacturer/Model
Dell XPS 8930
CPU
Intel I9-9900K
Memory
64GB
Graphics Card(s)
NVIDIA RTX 2060
Sound Card
NVIDIA High Definition Audio
Monitor(s) Displays
4k Samsung
Screen Resolution
3840 x 2160
Hard Drives
512GB NVMe, ADATA SU 800, 2TB HDD
Downloading rn
 

My Computer My Computer

At a glance

Windows 1115GB RAM
OS
Windows 11
Computer type
Laptop
Manufacturer/Model
HP
Memory
15GB RAM
Hard Drives
SSD 1TB
Browser
Chrome
Just rebooted to make sure my Halseo rescue drive (usb) still worked after the update. All OK there.
After returning to normal system after the re-boot noticed that along the bottom of the screen usually there was several widgets showing, this time the only one was the Weather.

Also, following the re-boot, got the dreaded 'Defender is off'.
 

My Computer My Computer

At a glance

Windows 11 Intel i5 10400 HD630 graphics chipi5-1040012 gbHD630 chipset
OS
Windows 11 Intel i5 10400 HD630 graphics chip
Computer type
PC/Desktop
Manufacturer/Model
HP
CPU
i5-10400
Memory
12 gb
Graphics Card(s)
HD630 chipset
Monitor(s) Displays
LG 24inch
Hard Drives
SSD, external usb drive 1tb for files/backups
Keyboard
wireless Logi
Mouse
ms 4000 wireless mouse
Internet Speed
10meg
Browser
Firefox
Antivirus
Defender
Other Info
Win11 Home 25h2 26200.9457 09/14/2026
Updated here! Everything is fine 😊
 

My Computer My Computer

At a glance

win 11 pro 25 h2
OS
win 11 pro 25 h2
Computer type
PC/Desktop
I wonder if I DISM/RestoreHealth works now.
 

My Computer My Computer

At a glance

Windows 11 Pro 25H2Gen 11 Core i516GB
OS
Windows 11 Pro 25H2
Computer type
Laptop
Manufacturer/Model
HP
CPU
Gen 11 Core i5
Memory
16GB
magilla said:
hmmm. Not being offered to my two machines that were successfully updated two days ago.
Click to expand...
My printer server updated on it's own, and I just updated this machine. I haven't checked the other machines, but I presume they'll get the updates since they're the same build as these.
Phirevixen said:
I wonder if I DISM/RestoreHealth works now.
Click to expand...
Nope!
 

My Computers My Computers

System One System Two Other systems

  • At a glance

    Win 11 Pro 25H2, Build 26200.9457Intel Core i5 14500, 14th Generation64GB DDR4GeForce RTX 4060
    OS
    Win 11 Pro 25H2, Build 26200.9457
    Computer type
    PC/Desktop
    Manufacturer/Model
    Home Brew
    CPU
    Intel Core i5 14500, 14th Generation
    Motherboard
    Gigabyte B760M G P WIFI
    Memory
    64GB DDR4
    Graphics Card(s)
    GeForce RTX 4060
    Sound Card
    Chipset Realtek
    Monitor(s) Displays
    LG 45" Ultragear & Acer 24" 1080p
    Screen Resolution
    5120x1440 & 1920x1080
    Hard Drives
    Crucial P310 2TB 2280 PCIe Gen4 3D NAND NVMe M.2 SSD (O/S)
    Silicon Power 2TB US75 NVMe PCIe Gen4 M.2 2280 SSD (backup)
    Crucial BX500 2TB 3D NAND (2nd backup)
    Seagate 4TB Ironwolf, rotating HDD secondary backup
    External off-line backup Drives: 2 NVMe 4TB drives in external enclosures
    PSU
    Thermaltake Toughpower GF3 750W
    Case
    LIAN LI LANCOOL 216 E-ATX PC Case
    Cooling
    Lots of fans!
    Keyboard
    Microsoft Comfort Curve 2000
    Mouse
    Logitech G305
    Internet Speed
    Verizon FiOS 1GB
    Browser
    Firefox
    Antivirus
    Malware Bytes & Windows Defender Security

  • At a glance

    Win 11 Pro 25H2, Build 26200.9168Intel Core i5 1440032GB DDR5Intel 700 Embedded GPU
    Operating System
    Win 11 Pro 25H2, Build 26200.9168
    Computer type
    PC/Desktop
    Manufacturer/Model
    Home Brew
    CPU
    Intel Core i5 14400
    Motherboard
    Gigabyte B760M DS3H AX
    Memory
    32GB DDR5
    Graphics card(s)
    Intel 700 Embedded GPU
    Sound Card
    Realtek Embedded
    Monitor(s) Displays
    27" HP 1080p
    Screen Resolution
    1920x1080
    Hard Drives
    Crucial P310 2TB NVMe Gen4 SSD
    Samsung EVO 990 2TB NVMe Gen4 SSD
    Samsung 2TB SATA SSD
    Seagate 4TB Ironwolf, rotating HDD secondary backup
    PSU
    Thermaltake Smart BM3 650W
    Case
    Okinos Micro ATX Case
    Cooling
    Fans
    Keyboard
    Microsoft Comfort Curve 2000
    Mouse
    Logitech G305
    Internet Speed
    Verizon FiOS 1GB
    Browser
    Firefox
    Antivirus
    Malware Bytes & Windows Defender Security
  • Nimo N171 17" Laptop, (Intel i3-1215U, 16GB RAM, 2TB NVMe, Win11 Pro)
    Acemagic Vista Mini PC V1 (Intel N150, 16GB RAM, 1TB NVMe, Win11 Pro)
    HP ENVY h8-1540t, (24GB RAM, 2TB SSD, 2TB HDD, Win11 Pro)
Updated 3 machines to the latest build. DISM and SFC scans went well. So far, no issues.
 

My Computers My Computers

System One System Two Other systems

  • At a glance

    Windows 11 Pro 25H2AMD Ryzen 9 7940HS32 GBRadeon 780M Graphics
    OS
    Windows 11 Pro 25H2
    Computer type
    PC/Desktop
    Manufacturer/Model
    Geekom AX7 Pro
    CPU
    AMD Ryzen 9 7940HS
    Memory
    32 GB
    Graphics Card(s)
    Radeon 780M Graphics
    Monitor(s) Displays
    Dell S2425H 24"
    Screen Resolution
    1920 x 1080
    Hard Drives
    2 TB NVMe SSD
    Internet Speed
    100 Mbs
    Browser
    Microsoft Edge / Firefox
    Antivirus
    F-Secure Security Suite
    Other Info
    All secure boot certificates updated to CA 2023
    Windows Production PCA 2011 certificate has been revoked.

  • At a glance

    Windows 11 Pro 25H212th Gen Intel Core i7-12700 processor (12-Co...16 GBIntel(R) UHD Graphics 770 with shared graphic...
    Operating System
    Windows 11 Pro 25H2
    Computer type
    PC/Desktop
    Manufacturer/Model
    Dell Inspiron 3910
    CPU
    12th Gen Intel Core i7-12700 processor (12-Core, 25M Cache, 2.1GHz to 4.8GHz)
    Motherboard
    Dell 0KHP4K
    Memory
    16 GB
    Graphics card(s)
    Intel(R) UHD Graphics 770 with shared graphics memory
    Monitor(s) Displays
    Dell 27" Monitor S2721DS,
    Screen Resolution
    QHD 2560 x 1440 @ 75 Hz
    Hard Drives
    1TB M.2, PCIe NVMe, SSD
    Internet Speed
    100 Mbps
    Browser
    Edge
    Antivirus
    F-Secure Security Suite
    Other Info
    All secure boot certificates updated to CA 2023
    Windows Production PCA 2011 certificate has been revoked.
  • HP Laptop 15-fd0xxx
    OS: Windows 11 Home 25H2
    Processor: 13th Gen Intel(R) Core(TM) i7-1355U (1.70 GHz), 10 Cores, 12 Logical Processors
    BIOS Version: AMI F.26 4/22/2026
    RAM: 16 GB
    SSD: 1 TB
    Screen Resolution: 1920 x 1080
    All secure boot certificates updated to CA 2023 by factory.
garlin said:
No.. The OOB is only to hotfix Remote Desktop, Hyper-V and audio. Otherwise it's the same KB as before, no other changes are made.
Click to expand...
Thank you Sir
 

My Computer My Computer

At a glance

Windows 11 Pro 25H2Gen 11 Core i516GB
OS
Windows 11 Pro 25H2
Computer type
Laptop
Manufacturer/Model
HP
CPU
Gen 11 Core i5
Memory
16GB
I actually use Remote Desktop, so I figured it might be useful for me.
 

My Computers My Computers

System One System Two Other systems

  • At a glance

    Win 11 Pro 25H2, Build 26200.9457Intel Core i5 14500, 14th Generation64GB DDR4GeForce RTX 4060
    OS
    Win 11 Pro 25H2, Build 26200.9457
    Computer type
    PC/Desktop
    Manufacturer/Model
    Home Brew
    CPU
    Intel Core i5 14500, 14th Generation
    Motherboard
    Gigabyte B760M G P WIFI
    Memory
    64GB DDR4
    Graphics Card(s)
    GeForce RTX 4060
    Sound Card
    Chipset Realtek
    Monitor(s) Displays
    LG 45" Ultragear & Acer 24" 1080p
    Screen Resolution
    5120x1440 & 1920x1080
    Hard Drives
    Crucial P310 2TB 2280 PCIe Gen4 3D NAND NVMe M.2 SSD (O/S)
    Silicon Power 2TB US75 NVMe PCIe Gen4 M.2 2280 SSD (backup)
    Crucial BX500 2TB 3D NAND (2nd backup)
    Seagate 4TB Ironwolf, rotating HDD secondary backup
    External off-line backup Drives: 2 NVMe 4TB drives in external enclosures
    PSU
    Thermaltake Toughpower GF3 750W
    Case
    LIAN LI LANCOOL 216 E-ATX PC Case
    Cooling
    Lots of fans!
    Keyboard
    Microsoft Comfort Curve 2000
    Mouse
    Logitech G305
    Internet Speed
    Verizon FiOS 1GB
    Browser
    Firefox
    Antivirus
    Malware Bytes & Windows Defender Security

  • At a glance

    Win 11 Pro 25H2, Build 26200.9168Intel Core i5 1440032GB DDR5Intel 700 Embedded GPU
    Operating System
    Win 11 Pro 25H2, Build 26200.9168
    Computer type
    PC/Desktop
    Manufacturer/Model
    Home Brew
    CPU
    Intel Core i5 14400
    Motherboard
    Gigabyte B760M DS3H AX
    Memory
    32GB DDR5
    Graphics card(s)
    Intel 700 Embedded GPU
    Sound Card
    Realtek Embedded
    Monitor(s) Displays
    27" HP 1080p
    Screen Resolution
    1920x1080
    Hard Drives
    Crucial P310 2TB NVMe Gen4 SSD
    Samsung EVO 990 2TB NVMe Gen4 SSD
    Samsung 2TB SATA SSD
    Seagate 4TB Ironwolf, rotating HDD secondary backup
    PSU
    Thermaltake Smart BM3 650W
    Case
    Okinos Micro ATX Case
    Cooling
    Fans
    Keyboard
    Microsoft Comfort Curve 2000
    Mouse
    Logitech G305
    Internet Speed
    Verizon FiOS 1GB
    Browser
    Firefox
    Antivirus
    Malware Bytes & Windows Defender Security
  • Nimo N171 17" Laptop, (Intel i3-1215U, 16GB RAM, 2TB NVMe, Win11 Pro)
    Acemagic Vista Mini PC V1 (Intel N150, 16GB RAM, 1TB NVMe, Win11 Pro)
    HP ENVY h8-1540t, (24GB RAM, 2TB SSD, 2TB HDD, Win11 Pro)
The same bugs might be floating in the RP and Insider builds, but they won't get an Out-of-Band. Instead the same fixes will be rolled into the RP and Insider build pipeline, and eventually show up in the next incremental builds.

MS policy is if a problem is so terrible that paid customers cannot wait for another Patch Tuesday, or even the next Preview Tuesday, Out-of-Bands are required until the problems are confirmed to be actually fixed. One time MS screwed up printing so bad it OOB'ed twice in a row since the first OOB didn't correct all of the reported issues.

If it's bad, the affected Windows teams have to work non-stop until the fix is delivered.

But alas File History remains broken...
 

My Computer My Computer

At a glance

Windows 7
OS
Windows 7
This problem with false Defender off notification showed up on another machine with public build after this update. So now I have 2 machines on public build with this problem. 😖🤬🤷‍♂️

Edition Windows 11 Pro
Version 25H2
Installed on ‎8/‎29/‎2025
OS build 26200.9457
Experience Windows Feature Experience Pack 1000.26100.360.0


1789427351068.webp

1789427419871.webp
1789427468944.webp
 

My Computer My Computer

At a glance

Windows 11 Pro 25H2Intel I9-9900K64GBNVIDIA RTX 2060
OS
Windows 11 Pro 25H2
Computer type
PC/Desktop
Manufacturer/Model
Dell XPS 8930
CPU
Intel I9-9900K
Memory
64GB
Graphics Card(s)
NVIDIA RTX 2060
Sound Card
NVIDIA High Definition Audio
Monitor(s) Displays
4k Samsung
Screen Resolution
3840 x 2160
Hard Drives
512GB NVMe, ADATA SU 800, 2TB HDD
None of my machines have had the issue with the virus protection false warning.
 

My Computers My Computers

System One System Two Other systems

  • At a glance

    Win 11 Pro 25H2, Build 26200.9457Intel Core i5 14500, 14th Generation64GB DDR4GeForce RTX 4060
    OS
    Win 11 Pro 25H2, Build 26200.9457
    Computer type
    PC/Desktop
    Manufacturer/Model
    Home Brew
    CPU
    Intel Core i5 14500, 14th Generation
    Motherboard
    Gigabyte B760M G P WIFI
    Memory
    64GB DDR4
    Graphics Card(s)
    GeForce RTX 4060
    Sound Card
    Chipset Realtek
    Monitor(s) Displays
    LG 45" Ultragear & Acer 24" 1080p
    Screen Resolution
    5120x1440 & 1920x1080
    Hard Drives
    Crucial P310 2TB 2280 PCIe Gen4 3D NAND NVMe M.2 SSD (O/S)
    Silicon Power 2TB US75 NVMe PCIe Gen4 M.2 2280 SSD (backup)
    Crucial BX500 2TB 3D NAND (2nd backup)
    Seagate 4TB Ironwolf, rotating HDD secondary backup
    External off-line backup Drives: 2 NVMe 4TB drives in external enclosures
    PSU
    Thermaltake Toughpower GF3 750W
    Case
    LIAN LI LANCOOL 216 E-ATX PC Case
    Cooling
    Lots of fans!
    Keyboard
    Microsoft Comfort Curve 2000
    Mouse
    Logitech G305
    Internet Speed
    Verizon FiOS 1GB
    Browser
    Firefox
    Antivirus
    Malware Bytes & Windows Defender Security

  • At a glance

    Win 11 Pro 25H2, Build 26200.9168Intel Core i5 1440032GB DDR5Intel 700 Embedded GPU
    Operating System
    Win 11 Pro 25H2, Build 26200.9168
    Computer type
    PC/Desktop
    Manufacturer/Model
    Home Brew
    CPU
    Intel Core i5 14400
    Motherboard
    Gigabyte B760M DS3H AX
    Memory
    32GB DDR5
    Graphics card(s)
    Intel 700 Embedded GPU
    Sound Card
    Realtek Embedded
    Monitor(s) Displays
    27" HP 1080p
    Screen Resolution
    1920x1080
    Hard Drives
    Crucial P310 2TB NVMe Gen4 SSD
    Samsung EVO 990 2TB NVMe Gen4 SSD
    Samsung 2TB SATA SSD
    Seagate 4TB Ironwolf, rotating HDD secondary backup
    PSU
    Thermaltake Smart BM3 650W
    Case
    Okinos Micro ATX Case
    Cooling
    Fans
    Keyboard
    Microsoft Comfort Curve 2000
    Mouse
    Logitech G305
    Internet Speed
    Verizon FiOS 1GB
    Browser
    Firefox
    Antivirus
    Malware Bytes & Windows Defender Security
  • Nimo N171 17" Laptop, (Intel i3-1215U, 16GB RAM, 2TB NVMe, Win11 Pro)
    Acemagic Vista Mini PC V1 (Intel N150, 16GB RAM, 1TB NVMe, Win11 Pro)
    HP ENVY h8-1540t, (24GB RAM, 2TB SSD, 2TB HDD, Win11 Pro)
gunrunnerjohn said:
None of my machines have had the issue with the virus protection false warning.
Click to expand...
I have that problem on multiple insider machines and also on 2 Public Build machines now. Microsoft confusing experiments. 😵‍💫🤷‍♂️
1789429066151.webp

And just got it again. 😵‍💫🤷‍♂️
1789537857546.webp

Join Windows Insider – Get early access to Windows 11 features & updates

Join the Windows Insider Program to preview Windows features, provide feedback, and shape what's coming next to Windows.
aka.ms

Join Windows Insider – Get early access to Windows 11 features & updates

Join the Windows Insider Program to preview Windows features, provide feedback, and shape what's coming next to Windows.
aka.ms


Defender “Off” False Notification Bug — Fix Status​

Microsoft has confirmed that the “Microsoft Defender Antivirus is turned off” pop‑ups you’re seeing are false alerts caused by a bug in recent Microsoft Defender Antivirus updates, not by a real shutdown of protection windowsforum.comwindowsforum.com+1.

What’s happening​

  • The bug can appear at Windows startup and intermittently afterward, even if Defender settings show it as active and real‑time protection is enabled windowsforum.comwindowsforum.com+1.
  • It can persist even if notification settings are disabled, making it feel like a real security issue Cyber Security NewsCyber Security News+1.
  • The antivirus engine is still running normally; the warning is only a UI bug Digital CitizenDigital Citizen.

Affected systems​

  • Windows 11: 23H2, 24H2, 25H2, 26H1
  • Windows 10: 21H2, 22H2, Enterprise LTSC 2016 & 2019
  • Windows Server: 2012, 2012 R2, 2016, 2019, 2022, 2025 Cyber Security NewsCyber Security News+1

How to verify protection​

Before ignoring the alert, check:

  1. Open Windows Security → Virus & threat protection.
  2. Confirm Real‑time protection is enabled.
  3. (Optional) Run Get-MpComputerStatus in PowerShell and check RealTimeProtectionEnabled — if it’s True, Defender is active whysogeek.comwhysogeek.com.

Fix timeline​

  • Microsoft has opened a release‑health advisory on August 28, 2026, and says it is working on a resolution windowsforum.comwindowsforum.com+1.
  • The fix will be delivered in a future Microsoft Defender Antivirus update, but no release date has been announced windowsforum.comwindowsforum.com+1.
  • Until then, the only safe action is to verify Defender’s status and ignore the popup if protection is confirmed active.
Bottom line: This is a known, confirmed bug, not a security failure. Microsoft is preparing a fix, but there’s no set date yet. For now, check Windows Security to confirm protection is still active, then wait for the Defender update that will correct the notification.
 
Last edited:

My Computer My Computer

At a glance

Windows 11 Pro 25H2Intel I9-9900K64GBNVIDIA RTX 2060
OS
Windows 11 Pro 25H2
Computer type
PC/Desktop
Manufacturer/Model
Dell XPS 8930
CPU
Intel I9-9900K
Memory
64GB
Graphics Card(s)
NVIDIA RTX 2060
Sound Card
NVIDIA High Definition Audio
Monitor(s) Displays
4k Samsung
Screen Resolution
3840 x 2160
Hard Drives
512GB NVMe, ADATA SU 800, 2TB HDD
Installed,
DISM /Online /Cleanup-Image /ScanHealth and SFC /Scannow no issues.
Disk Clean-up reported 190MB of Windows Update Files.
DISM /Online /Cleanup-Image /AnalyzeComponentStore reported 1 extra recoverable package.
DISM /Online /Cleanup-Image /StartComponentCleanup.
Disk Clean-up reported 0MB of Windows Update Files.
DISM /Online /Cleanup-Image /ScanHealth and SFC /Scannow no issues.
 

My Computer My Computer

At a glance

Windows 11AMD Ryzen 8700G64 GBOnboard
OS
Windows 11
Computer type
PC/Desktop
Manufacturer/Model
Generic
CPU
AMD Ryzen 8700G
Motherboard
Gigabyte B650 UD AC
Memory
64 GB
Graphics Card(s)
Onboard
Sound Card
Onboard
Monitor(s) Displays
Del U2723QE
Screen Resolution
3840 x 2160
Hard Drives
Corsiar MP600 1TB
PSU
Silverstone 750 GOLD
Case
Silverstone FARA 513
EB2XR6 said:
Disk Clean-up reported 190MB
Click to expand...


If after running Disk Cleanup, it still shows 190MB of stuff, run this...

Dism.exe /online /Cleanup-Image /StartComponentCleanup /ResetBase
 

My Computers My Computers

System One System Two

  • At a glance

    Win 11 Home ♦♦♦26300.9457 ♦♦♦♦♦♦♦26H2AMD Ryzen 7 3700XG.Skill (F4-3200C14D-16GTZKW)EVGA RTX 2070 (08G-P4-2171-KR)
    OS
    Win 11 Home ♦♦♦26300.9457 ♦♦♦♦♦♦♦26H2
    Computer type
    PC/Desktop
    Manufacturer/Model
    Built by Ghot® [May 2020]
    CPU
    AMD Ryzen 7 3700X
    Motherboard
    Asus Pro WS X570-ACE (BIOS 5302)
    Memory
    G.Skill (F4-3200C14D-16GTZKW)
    Graphics Card(s)
    EVGA RTX 2070 (08G-P4-2171-KR)
    Sound Card
    Realtek ALC1220P / ALC S1220A
    Monitor(s) Displays
    Dell U3011 30"
    Screen Resolution
    2560 x 1600
    Hard Drives
    2x Samsung 860 EVO 500GB,
    WD 4TB Black FZBX - SATA III,
    WD 8TB Black FZBX - SATA III,
    DRW-24B1ST CD/DVD Burner
    PSU
    PC Power & Cooling 750W Quad EPS12V
    Case
    Cooler Master ATCS 840 Tower
    Cooling
    CM Hyper 212 EVO (push/pull)
    Keyboard
    Ducky DK9008 Shine II Blue LED
    Mouse
    Logitech Optical M-100
    Internet Speed
    300/300
    Browser
    Firefox (latest)
    Antivirus
    Bitdefender Total Security
    Other Info
    Speakers: Klipsch Pro Media 2.1

  • At a glance

    Windows XP Pro 32bit w/SP3AMD Athlon 64 X2 5000+ (OC'd @ 3.2Ghz)TWIN2X2048-6400C4DHX (2 x 1GB, DDR2 800)EVGA 256-P2-N758-TR GeForce 8600GT SSC
    Operating System
    Windows XP Pro 32bit w/SP3
    Computer type
    PC/Desktop
    Manufacturer/Model
    Built by Ghot® (not in use)
    CPU
    AMD Athlon 64 X2 5000+ (OC'd @ 3.2Ghz)
    Motherboard
    ASUS M2N32-SLI Deluxe Wireless Edition
    Memory
    TWIN2X2048-6400C4DHX (2 x 1GB, DDR2 800)
    Graphics card(s)
    EVGA 256-P2-N758-TR GeForce 8600GT SSC
    Sound Card
    Onboard
    Monitor(s) Displays
    ViewSonic G90FB Black 19" Professional (CRT)
    Screen Resolution
    up to 2048 x 1536
    Hard Drives
    WD 36GB 10,000rpm Raptor SATA
    Seagate 80GB 7200rpm SATA
    Lite-On LTR-52246S CD/RW
    Lite-On LH-18A1P CD/DVD Burner
    PSU
    PC Power & Cooling Silencer 750 Quad EPS12V
    Case
    Generic Beige case, 80mm fans
    Cooling
    ZALMAN 9500A 92mm CPU Cooler
    Keyboard
    Logitech Classic Keybooard 200
    Mouse
    Logitech Optical M-BT96a
    Internet Speed
    300/300
    Browser
    Firefox 3.x ??
    Antivirus
    Symantec (Norton)
    Other Info
    Still assembled, still runs. Haven't turned it on for 15 years?
Ghot said:
I don't have that setting turned ON, but I still got the update.
Click to expand...
Same here - setting OFF, update offered but there's nothing in it for me so i think I'll wait until the October update.
 

My Computer My Computer

At a glance

Windows 11 ProIntel Core i5 1440032GBPalit GeForce RTX 3050 Dual 8GB GPU
OS
Windows 11 Pro
Computer type
PC/Desktop
Manufacturer/Model
Chillblast
CPU
Intel Core i5 14400
Motherboard
ASUS TUF Gaming B760M-PLUS WiFi II
Memory
32GB
Graphics Card(s)
Palit GeForce RTX 3050 Dual 8GB GPU
Sound Card
Integrated
Monitor(s) Displays
HP S2331 & ASUS VS239
Screen Resolution
1920x1080
Hard Drives
WD Blue SSD 500GB + 2 x 2TB Seagate BarraCuda
PSU
850W Corsair
Case
Fractel Define 7
Cooling
Standard - no additional
Keyboard
Kensington Value (for now)
Mouse
Tecknet Optical
Browser
Edge and Chrome
Antivirus
Norton Security 360 Advanced
VBF said:
Same here - setting OFF, update offered but there's nothing in it for me so i think I'll wait until the October update.
Click to expand...


Out-of-band updates "fix" something in the monthly update.
They are not preview updates, like we see at the end of the month.

I recommend installing any out-of-band updates that are released.
 

My Computers My Computers

System One System Two

  • At a glance

    Win 11 Home ♦♦♦26300.9457 ♦♦♦♦♦♦♦26H2AMD Ryzen 7 3700XG.Skill (F4-3200C14D-16GTZKW)EVGA RTX 2070 (08G-P4-2171-KR)
    OS
    Win 11 Home ♦♦♦26300.9457 ♦♦♦♦♦♦♦26H2
    Computer type
    PC/Desktop
    Manufacturer/Model
    Built by Ghot® [May 2020]
    CPU
    AMD Ryzen 7 3700X
    Motherboard
    Asus Pro WS X570-ACE (BIOS 5302)
    Memory
    G.Skill (F4-3200C14D-16GTZKW)
    Graphics Card(s)
    EVGA RTX 2070 (08G-P4-2171-KR)
    Sound Card
    Realtek ALC1220P / ALC S1220A
    Monitor(s) Displays
    Dell U3011 30"
    Screen Resolution
    2560 x 1600
    Hard Drives
    2x Samsung 860 EVO 500GB,
    WD 4TB Black FZBX - SATA III,
    WD 8TB Black FZBX - SATA III,
    DRW-24B1ST CD/DVD Burner
    PSU
    PC Power & Cooling 750W Quad EPS12V
    Case
    Cooler Master ATCS 840 Tower
    Cooling
    CM Hyper 212 EVO (push/pull)
    Keyboard
    Ducky DK9008 Shine II Blue LED
    Mouse
    Logitech Optical M-100
    Internet Speed
    300/300
    Browser
    Firefox (latest)
    Antivirus
    Bitdefender Total Security
    Other Info
    Speakers: Klipsch Pro Media 2.1

  • At a glance

    Windows XP Pro 32bit w/SP3AMD Athlon 64 X2 5000+ (OC'd @ 3.2Ghz)TWIN2X2048-6400C4DHX (2 x 1GB, DDR2 800)EVGA 256-P2-N758-TR GeForce 8600GT SSC
    Operating System
    Windows XP Pro 32bit w/SP3
    Computer type
    PC/Desktop
    Manufacturer/Model
    Built by Ghot® (not in use)
    CPU
    AMD Athlon 64 X2 5000+ (OC'd @ 3.2Ghz)
    Motherboard
    ASUS M2N32-SLI Deluxe Wireless Edition
    Memory
    TWIN2X2048-6400C4DHX (2 x 1GB, DDR2 800)
    Graphics card(s)
    EVGA 256-P2-N758-TR GeForce 8600GT SSC
    Sound Card
    Onboard
    Monitor(s) Displays
    ViewSonic G90FB Black 19" Professional (CRT)
    Screen Resolution
    up to 2048 x 1536
    Hard Drives
    WD 36GB 10,000rpm Raptor SATA
    Seagate 80GB 7200rpm SATA
    Lite-On LTR-52246S CD/RW
    Lite-On LH-18A1P CD/DVD Burner
    PSU
    PC Power & Cooling Silencer 750 Quad EPS12V
    Case
    Generic Beige case, 80mm fans
    Cooling
    ZALMAN 9500A 92mm CPU Cooler
    Keyboard
    Logitech Classic Keybooard 200
    Mouse
    Logitech Optical M-BT96a
    Internet Speed
    300/300
    Browser
    Firefox 3.x ??
    Antivirus
    Symantec (Norton)
    Other Info
    Still assembled, still runs. Haven't turned it on for 15 years?
Ghot said:
Out-of-band updates "fix" something in the monthly update.
They are not preview updates, like we see at the end of the month.

I recommend installing any out-of-band updates that are released.
Click to expand...
OK - thanks for responding - i said what i did because, looking at the list describing the update, none of the 4 Improvements are related to anything i use.
I suppose the Servicing Stack update could be considered important.
I'll update it in the next few hours
 

My Computer My Computer

At a glance

Windows 11 ProIntel Core i5 1440032GBPalit GeForce RTX 3050 Dual 8GB GPU
OS
Windows 11 Pro
Computer type
PC/Desktop
Manufacturer/Model
Chillblast
CPU
Intel Core i5 14400
Motherboard
ASUS TUF Gaming B760M-PLUS WiFi II
Memory
32GB
Graphics Card(s)
Palit GeForce RTX 3050 Dual 8GB GPU
Sound Card
Integrated
Monitor(s) Displays
HP S2331 & ASUS VS239
Screen Resolution
1920x1080
Hard Drives
WD Blue SSD 500GB + 2 x 2TB Seagate BarraCuda
PSU
850W Corsair
Case
Fractel Define 7
Cooling
Standard - no additional
Keyboard
Kensington Value (for now)
Mouse
Tecknet Optical
Browser
Edge and Chrome
Antivirus
Norton Security 360 Advanced
VBF said:
I suppose the Servicing Stack update could be considered important.
Click to expand...
There is no new SSU. MS doesn't take the opportunity to sneak in more changes than is absolutely necessary to fix the 4 reported issues.
 

My Computer My Computer

At a glance

Windows 7
OS
Windows 7
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