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:



Check Windows Updates


UUP Dump:

64-bit ISO download:

ARM64 ISO download:

 
Last edited:
Edition Windows 11 Pro
Version 25H2
Installed on ‎20.‎9.‎2025.
OS build 26200.9457
Experience Windows Feature Experience Pack 1000.26100.360.0
 

My Computer My Computer

At a glance

W11 Pro and Insider DevAMD Ryzen 9 7900x2x16GB Kingston 6000MHz, Cl 32 @ 6200MHz Cl30Gigabyte Rx 6600XT Gaming OC 8G Pro
OS
W11 Pro and Insider Dev
Computer type
PC/Desktop
Manufacturer/Model
Home brewed
CPU
AMD Ryzen 9 7900x
Motherboard
ASROCK b650 PRO RS
Memory
2x16GB Kingston 6000MHz, Cl 32 @ 6200MHz Cl30
Graphics Card(s)
Gigabyte Rx 6600XT Gaming OC 8G Pro
Sound Card
MB, Realtek Ac1220p
Monitor(s) Displays
3 x 27"
Screen Resolution
1080p
Hard Drives
Kingston KC3000. 1TBSamsung 970 evo Plus 500GB, Crucial P1 NVMe 1TB, Lexar NVMe 2 TB, Silicon Power M.2 SATA 500GB
PSU
Seasonic 750W
Case
Custom Raidmax
Cooling
Arctic Liquid Freezer III 360mm
Internet Speed
20/19 mbps
They seem to be rushing this out in a hurry.
Just went to make a coffee, came back to find the "Your Device needs to restart" icon on the Taskbar.
It rebooted twice during the restart.
'SFC' and 'DISM' checks all good.
1789409308413.webp

Dave.
 

My Computer My Computer

At a glance

Windows 11 Pro 25H2 build 26200.9457AMD Ryzen 7 7800X3D 8-Core ProcessorCorsair Vengeance 32GB (2 X 16 GB, DDR 5)Sapphire Nitro AMD Radeon RX 9070 XT, 16GB
OS
Windows 11 Pro 25H2 build 26200.9457
Computer type
PC/Desktop
Manufacturer/Model
Homemade in Feb 2025.
CPU
AMD Ryzen 7 7800X3D 8-Core Processor
Motherboard
MSI MAG B650 Tomahawk WiFi
Memory
Corsair Vengeance 32GB (2 X 16 GB, DDR 5)
Graphics Card(s)
Sapphire Nitro AMD Radeon RX 9070 XT, 16GB
Sound Card
Realtek ALC 4080 on Motherboard
Monitor(s) Displays
LG E2442 on HDMI
Screen Resolution
1920 X 1080, 60Hz
Hard Drives
Silicon Power XS70 2TB M2 2280, Western Digital 1TB HDD, Seagate 500 GB HDD, Crucial 250GB SSD.
PSU
Corsair RM850x
Case
Very old ATX
Cooling
be quite! PURE ROCK SLIM 2
Keyboard
Logitech K120 wired USB
Mouse
Logitech M570 wirless trackerball
Internet Speed
300 Mbps down and 70 Mbps up from a TP-Link Archer NX210 5G sim card router
Browser
Firefox 155.0.1
Antivirus
Just Windows Defender
@Brink What 26H2 channel is this for?
 

My Computers My Computers

  • At a glance

    Windows 11 ProIntel Core i9 14900K 5800/4500 P/E96GB (2x48) G.skill Ripjaws 6800Asus ROG Strix 4070 Ti OC
    OS
    Windows 11 Pro
    Computer type
    PC/Desktop
    Manufacturer/Model
    DIY Photoshop/Audio/Game/tinker
    CPU
    Intel Core i9 14900K 5800/4500 P/E
    Motherboard
    Asus ROG Maximus Z790 Dark Hero
    Memory
    96GB (2x48) G.skill Ripjaws 6800
    Graphics Card(s)
    Asus ROG Strix 4070 Ti OC
    Sound Card
    B&W 606 S3 speakers; Audiolabs 7000a integrated amp; RSL 10S Mk2 sub
    Monitor(s) Displays
    Eizo CG2730 ColorEdge, ViewSonic VP2768
    Screen Resolution
    2560 x 1440 x 2
    Hard Drives
    nvme: WDC SN850X 4TB, SN850 1TB, SK-Hynix 2 TB P41
    Spinners: Sabrent USB-C DS-SC5B 5-bay docking station, 6TB WDC Black, 6TB Ironwolf Pro 2x 2TB WDC Black
    PSU
    850W Seasonic Vertex PX-850
    Case
    FD North XL Mesh, Black Walnut
    Cooling
    EK Nucleus black 360 AIO w/Phanteks T30 fans; 2 Noctua NF-A14 Chromax ; T30 for memory
    Keyboard
    Keychron Q3 Max TKL w/GMK Redsuns Red Samuri keycaps
    Mouse
    Logitech G305 wireless gaming
    Internet Speed
    575 Mb/s down | 25 Mb/s up
    Browser
    Firefox
    Antivirus
    Defender, Macrium Reflect X
    Other Info
    Phangkey Amaterasu V2 Desk Mat
  • At a glance

    Apple M1
    Computer type
    Laptop
    Manufacturer/Model
    💻 Apple 13" Macbook Pro 2020 (m1)
    CPU
    Apple M1
    Screen Resolution
    2560x1600
    Browser
    Firefox
@Brink What 26H2 channel is this for?

This 26H2 is for the retail channel even though it's technically only officially released via RP below.

Most likely 26H2 will officially hit retail with 24H2 end of support.

 

My Computers My Computers

  • At a glance

    Windows 11 Pro for WorkstationsIntel i7-8700K 5 GHz64 GB (4x16GB) G.SKILL TridentZ RGB DDR4 3600...ASUS ROG-STRIX-GTX1080TI-O11G-GAMING (11GB GD...
    OS
    Windows 11 Pro for Workstations
    Computer type
    PC/Desktop
    Manufacturer/Model
    Custom self build
    CPU
    Intel i7-8700K 5 GHz
    Motherboard
    ASUS ROG Maximus XI Formula Z390
    Memory
    64 GB (4x16GB) G.SKILL TridentZ RGB DDR4 3600 MHz (F4-3600C18D-32GTZR)
    Graphics Card(s)
    ASUS ROG-STRIX-GTX1080TI-O11G-GAMING (11GB GDDR5X)
    Sound Card
    Integrated Digital Audio (S/PDIF)
    Monitor(s) Displays
    2 x Samsung Odyssey G75 27"
    Screen Resolution
    2560x1440
    Hard Drives
    1TB Samsung 990 PRO M.2,
    4TB Samsung 990 PRO M.2,
    TerraMaster F8 SSD Plus NAS
    PSU
    Seasonic Prime Titanium 850W
    Case
    Thermaltake Core P3 wall mounted
    Cooling
    Corsair Hydro H115i
    Keyboard
    Amazon Basics Wired Full Keyboard MD005
    Mouse
    Logitech MX Master 4
    Internet Speed
    2 Gbps Download and 100 Mbps Upload
    Browser
    Chrome and Edge
    Antivirus
    Microsoft Defender
    Other Info
    Logitech Z625 speaker system,
    Logitech BRIO 4K Pro webcam,
    HP Color LaserJet Pro MFP M477fdn,
    CyberPower CP1500PFCLCD
    Galaxy S23 Plus phone
  • At a glance

    Windows 11 ProSnapdragon X Elite (12 core) 3.42 GHz16 GB LPDDR5x-7467 MHz
    Operating System
    Windows 11 Pro
    Computer type
    Laptop
    Manufacturer/Model
    Surface Laptop 7 Copilot+ PC
    CPU
    Snapdragon X Elite (12 core) 3.42 GHz
    Memory
    16 GB LPDDR5x-7467 MHz
    Monitor(s) Displays
    15" HDR
    Screen Resolution
    2496 x 1664
    Hard Drives
    1 TB SSD
    Internet Speed
    Wi-Fi 7 and Bluetooth 5.4
    Browser
    Chrome and Edge
    Antivirus
    Microsoft Defender
This 26H2 is for the retail channel even though it's technically only officially released via RP below.

Most likely 26H2 will officially hit retail with 24H2 end of support.


Yeah the RP is a higher version. Kind of confusing (not your fault).
 

My Computers My Computers

  • At a glance

    Windows 11 ProIntel Core i9 14900K 5800/4500 P/E96GB (2x48) G.skill Ripjaws 6800Asus ROG Strix 4070 Ti OC
    OS
    Windows 11 Pro
    Computer type
    PC/Desktop
    Manufacturer/Model
    DIY Photoshop/Audio/Game/tinker
    CPU
    Intel Core i9 14900K 5800/4500 P/E
    Motherboard
    Asus ROG Maximus Z790 Dark Hero
    Memory
    96GB (2x48) G.skill Ripjaws 6800
    Graphics Card(s)
    Asus ROG Strix 4070 Ti OC
    Sound Card
    B&W 606 S3 speakers; Audiolabs 7000a integrated amp; RSL 10S Mk2 sub
    Monitor(s) Displays
    Eizo CG2730 ColorEdge, ViewSonic VP2768
    Screen Resolution
    2560 x 1440 x 2
    Hard Drives
    nvme: WDC SN850X 4TB, SN850 1TB, SK-Hynix 2 TB P41
    Spinners: Sabrent USB-C DS-SC5B 5-bay docking station, 6TB WDC Black, 6TB Ironwolf Pro 2x 2TB WDC Black
    PSU
    850W Seasonic Vertex PX-850
    Case
    FD North XL Mesh, Black Walnut
    Cooling
    EK Nucleus black 360 AIO w/Phanteks T30 fans; 2 Noctua NF-A14 Chromax ; T30 for memory
    Keyboard
    Keychron Q3 Max TKL w/GMK Redsuns Red Samuri keycaps
    Mouse
    Logitech G305 wireless gaming
    Internet Speed
    575 Mb/s down | 25 Mb/s up
    Browser
    Firefox
    Antivirus
    Defender, Macrium Reflect X
    Other Info
    Phangkey Amaterasu V2 Desk Mat
  • At a glance

    Apple M1
    Computer type
    Laptop
    Manufacturer/Model
    💻 Apple 13" Macbook Pro 2020 (m1)
    CPU
    Apple M1
    Screen Resolution
    2560x1600
    Browser
    Firefox
They really took me by surprise. An update, then three restarts, and that was it. No problems at all. Let’s just hope it stays that way.
 

My Computer My Computer

At a glance

Windows 11 Pro 25H2 build 26200.9457AMD Ryzen 7 7700XRAM: 64 GB DDR5AMD Radeon RX 7800 XT (16 GB)
OS
Windows 11 Pro 25H2 build 26200.9457
Computer type
PC/Desktop
Manufacturer/Model
Custom build (Gigabyte)
CPU
AMD Ryzen 7 7700X
Motherboard
Gigabyte B650M GAMING X AX
Memory
RAM: 64 GB DDR5
Graphics Card(s)
AMD Radeon RX 7800 XT (16 GB)
Sound Card
Realtek (onboard)
Monitor(s) Displays
Samsung
Screen Resolution
1920 x 1080
Hard Drives
Samsung 990 PRO 1 TB (NVM-e),
Keyboard
Logitech MX Master
Mouse
Logitech MX Master 3S
Internet Speed
13ms/250Mbps/25Mbps
Browser
Microsoft Edge
Antivirus
Bitdefender
Other Info
UEFI, Secure Boot ON, TPM 2.0 ON
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