Insider KB5124137 Windows 11 Insider Experimental (26H2) build 26340.9502 - Sept. 18



 Microsoft Support:

Changes and improvements gradually being rolled out

[Accessibility - Mouse indicator]​

  • We're introducing a sleeker new animation for the Mouse indicator. You can enable this animation under Accessibility settings. We've also added the option to keep the indicator activated until you press the Esc key.

[Magnifier]​

  • A new contrast theme toggle for a lower-glare screen. If bright screens are uncomfortable, many people use color inversion to reduce glare. However, inversion changes everything on screen, including photos, charts, and videos. With this update, we're introducing a new contrast theme toggle in Magnifier.
  • Reduce glare with a single toggle. Turn on a contrast theme directly from the Magnifier toolbar for a more comfortable viewing experience.
  • Choose the contrast theme that works best for you. The dark theme is applied by default, and you can choose which contrast theme the toggle uses under Settings > Accessibility > Magnifier.
  • Photos, videos, and charts keep their original colors. Unlike color inversion, the contrast theme recolors the interface without touching your photos, charts, or videos, so they keep their real colors.
  • Color inversion is still here. This isn't a replacement. If you use inversion today, it works exactly as it always has. The contrast theme is a separate, purpose-built option to reduce glare when you want a darker interface without inverting colors.


    UI showing the new contrast theme toggle in Magnifier.
    UI showing the new contrast theme toggle in Magnifier.

    UI showing contrast theme settings for Magnifier.
    UI showing contrast theme settings for Magnifier.

[Cloud rebuild]​

  • We're updating Cloud rebuild, the recovery option that restores a Windows 11 PC to a clean, known-good state by performing a full OS reinstall, with two additions.
  • Cloud rebuild can now sanitize the device's drives as part of the rebuild. When you start a rebuild in WinRE, choose Remove files if you're keeping the PC, or Remove & sanitize files before recycling, returning, or reassigning it. The sanitize option uses the storage hardware's erase capability to securely erase data before Windows is reinstalled and is irreversible.
  • IT administrators can now configure and start a Cloud rebuild remotely through the Recovery CSP, using either the currently installed build or a target build you specify.


    UI showing new Cloud rebuild file removal options.
    UI showing new Cloud rebuild file removal options.

[Live Captions]​

  • We're improving Live Captions with a new Include Screen Reader audio setting, which is off by default. With the setting off, Live Captions won't transcribe audio from screen readers such as Narrator, JAWS, and NVDA, keeping captions focused on microphone and system audio.

[Hyper-V]​

  • Fixed an issue where some applications that used HCS-managed virtual machines experienced issues when sharing host folders with Linux VMs using Plan9. Folders shared from the Windows host using Plan9 didn't appear or couldn't be accessed in the guest environment.

[Other]​

  • Fixed an issue where backing up using File History unexpectedly failed with an error saying, "No usable drives found."

Reminders for Windows Insiders in the Experimental channel

  • Updates are based on Windows 11, version 26H2 via an enablement package (Build 26340.9502).
  • Many features are rolled out using Controlled Feature Rollout technology, starting with a subset of Insiders and ramping up over time. We monitor feedback to see how they land before pushing them out to everyone in this channel.
  • The desktop watermark shown at the lower right corner of the desktop is normal for Windows Insider pre-release builds.
  • Features and experiences included in these builds might never get released as we try out different concepts and get feedback. Features might change over time, be removed, or replaced and never get released beyond Windows Insiders. Some of these features and experiences could show up in future Windows releases when they're ready.
  • Some features in active development we preview with Windows Insiders might not be fully localized, and localization will happen over time as features are finalized. As you see issues with localization in your language, report those issues to us via Feedback Hub.
  • Check out Flight Hub for a complete look at what build is in which Insider channel.


 Source:



Check Windows Updates


ISO from Microsoft:



UUP Dump:

64-bit ISO download:

ARM64 ISO download:

 
Last edited:
And what is this ridiculous idea of Cloud Rebuild?
What about local rebuild or restore of a backup? Why do I need to use a third-party software for that?
I hope they don't plan to drop the old Image Backup and Restore that is done on local drives.
I really think that relying on the cloud is the worst idea they could ever come up with. 😂🤬🤷‍♂️
Cloud rebuild isn't for you. It's for the casual user who doesn't know about full backups, and didn't prepare any recovery media.

It assumes something corrupted the Windows volume (like a recent update or user tampering), but otherwise the system disk is bootable. Boot into WinRE, download an entire install image into temp, and basically re-install Windows for you.

If MS can teach DISM to download GB's of source data to repair your Windows, the same thing can be done for WinRE.
Something is better than nothing.
 

My Computer My Computer

At a glance

Windows 7
OS
Windows 7
Build 26340.9502 installed without a hitch, an extremely quick update through the usual WU cumulative install, a very sweet time of ~2 minutes including reboots...:)
 

My Computer My Computer

At a glance

Win11 RP channel for 26H2 buildsAMD R7 7800X3DGSkill 2x16GB @ 6400MT/sXFX 9070 XT SWIFT tri-fan (PCIe5.0)
OS
Win11 RP channel for 26H2 builds
Computer type
PC/Desktop
Manufacturer/Model
a cherry-picked assembly
CPU
AMD R7 7800X3D
Motherboard
MSI x870 Tomahawk Wi-Fi, 8-layer, 2 oz copper, server PCB
Memory
GSkill 2x16GB @ 6400MT/s
Graphics Card(s)
XFX 9070 XT SWIFT tri-fan (PCIe5.0)
Sound Card
Creative Labs G8 USB External Sound device, Gaming DAC, Sound Card & Earphone AMP.. HIGHLY RECOMMENDED, btw. Totally changed my opinion of external USB sound. I like!...;)
Monitor(s) Displays
Philips 42" OLED @ 4k
Screen Resolution
3840x2160
Hard Drives
*Boot: Samsung 980 Pro 2 TB NVMe (PCIe4x4)
*Samsung 980 EVO NVMe 500GB (PCIe 4x4)
*Kingston SNV3S2000G 2TB NVMe (PCIe4x4)
*Samsung 960 EVO 250GB NVMe(PCIe3x2)
*8TB Toshiba x300 HDD
*ST4000DM004 S3 4TB HDD
PSU
Gigabyte 850W Gold, Rev 2
Case
Lian Li Lancool 217, white, with wood trim, very nice looking--tired of black, 5-fans standard
Cooling
Air coutesy Lian Li
Keyboard
Cherry MX 2.0S RGB
Mouse
Razer Basilisk V3 24k DPI
Internet Speed
~950Mbps down and up!
Browser
Firefox x64 DE
Antivirus
Defender
Other Info
Great New system. Exceeds my expectations by quite a bit, btw. I love the USB G8 SoundBlaster, it's quite an improvement over the G6!
26340.xxxx is the worst of all insiders builds that I have installed on my machines.
They must be really drunk at Microsoft! This build sucks
And what is this ridiculous idea of Cloud Rebuild?
What about local rebuild or restore of a backup? Why do I need to use a third-party software for that?
I hope they don't plan to drop the old Image Backup and Restore that is done on local drives.
I really think that relying on the cloud is the worst idea they could ever come up with. 😂🤬🤷‍♂️

They are not "relying" on the cloud at all. They are simply introducing a new feature option relative to the cloud for those who might want it for some reason. I will not be using it...;) All the usual backup and restore options continue to function, as do third-party backup/restore programs like my favorite, Macrium Reflect. So you can relax. The sky has yet to fall, thankfully...;)

As an aside, the 26340 Experimental branch has turned out to be my favorite branch thus far. It's stable enough to run on bare metal without a problem, and I like the feature sets, including Feature Flags, which is one of my all-time Insider favorites!
26340.9502  2026-09-19 150034.webp
 
Last edited:

My Computer My Computer

At a glance

Win11 RP channel for 26H2 buildsAMD R7 7800X3DGSkill 2x16GB @ 6400MT/sXFX 9070 XT SWIFT tri-fan (PCIe5.0)
OS
Win11 RP channel for 26H2 builds
Computer type
PC/Desktop
Manufacturer/Model
a cherry-picked assembly
CPU
AMD R7 7800X3D
Motherboard
MSI x870 Tomahawk Wi-Fi, 8-layer, 2 oz copper, server PCB
Memory
GSkill 2x16GB @ 6400MT/s
Graphics Card(s)
XFX 9070 XT SWIFT tri-fan (PCIe5.0)
Sound Card
Creative Labs G8 USB External Sound device, Gaming DAC, Sound Card & Earphone AMP.. HIGHLY RECOMMENDED, btw. Totally changed my opinion of external USB sound. I like!...;)
Monitor(s) Displays
Philips 42" OLED @ 4k
Screen Resolution
3840x2160
Hard Drives
*Boot: Samsung 980 Pro 2 TB NVMe (PCIe4x4)
*Samsung 980 EVO NVMe 500GB (PCIe 4x4)
*Kingston SNV3S2000G 2TB NVMe (PCIe4x4)
*Samsung 960 EVO 250GB NVMe(PCIe3x2)
*8TB Toshiba x300 HDD
*ST4000DM004 S3 4TB HDD
PSU
Gigabyte 850W Gold, Rev 2
Case
Lian Li Lancool 217, white, with wood trim, very nice looking--tired of black, 5-fans standard
Cooling
Air coutesy Lian Li
Keyboard
Cherry MX 2.0S RGB
Mouse
Razer Basilisk V3 24k DPI
Internet Speed
~950Mbps down and up!
Browser
Firefox x64 DE
Antivirus
Defender
Other Info
Great New system. Exceeds my expectations by quite a bit, btw. I love the USB G8 SoundBlaster, it's quite an improvement over the G6!
HOLY CRAP - I thought my Huawei Matebook E had died with this build! Other than the Huawei logo on first power on there was NOTHING on screen... totally black. I thought the screen had died so I tapped CAPS LOCK and it lit up... so held down power and rebooted - and voila - it booted up Windows with the welcome NOISE but no picture still.
Thank goodness for F8 is all I can say. I went to troubleshot and tried a roll-back. That didn't work as apparently SOMETHING had been installed this morning at 11.20 (after this update) and that was the roll-back point. I tried it anyway to no avail.
So back to F8 I go and do troubleshoot again, and uninstal updates - there was a 'quality update' that uninstalled, and a 'feature update' that failed on uninstall. Anyway a reboot and STILL black!! I clicked the enter key several (well bashed it more than several methinks in anger LOL) and the Matebook rebooted and the screen came back! Now all seems normal again. I am now back on build 9482.... WTF Microsoft!
 

My Computer My Computer

At a glance

W11 ProIntel(R) Core(TM) i7-477016GBIntel HD 4600 & GeForce GT 750M
OS
W11 Pro
Computer type
PC/Desktop
Manufacturer/Model
Dell XPS One 2720
CPU
Intel(R) Core(TM) i7-4770
Motherboard
Dell
Memory
16GB
Graphics Card(s)
Intel HD 4600 & GeForce GT 750M
Sound Card
Realtek HD Audio
Monitor(s) Displays
27"
Screen Resolution
2560*1440
Hard Drives
512GB SSD boot drive connected via mSATA card
2TB SSD Data Drive
Case
AIO
Internet Speed
1GB Fibre
Antivirus
Microsoft
HOLY CRAP - I thought my Huawei Matebook E had died with this build! Other than the Huawei logo on first power on there was NOTHING on screen... totally black. I thought the screen had died so I tapped CAPS LOCK and it lit up... so held down power and rebooted - and voila - it booted up Windows with the welcome NOISE but no picture still.
Thank goodness for F8 is all I can say. I went to troubleshot and tried a roll-back. That didn't work as apparently SOMETHING had been installed this morning at 11.20 (after this update) and that was the roll-back point. I tried it anyway to no avail.
So back to F8 I go and do troubleshoot again, and uninstal updates - there was a 'quality update' that uninstalled, and a 'feature update' that failed on uninstall. Anyway a reboot and STILL black!! I clicked the enter key several (well bashed it more than several methinks in anger LOL) and the Matebook rebooted and the screen came back! Now all seems normal again. I am now back on build 9482.... WTF Microsoft!
It's from 2013 ?
 

My Computer My Computer

At a glance

26200.8037i5-11400F32GBGeforce GT-1030
OS
26200.8037
Computer type
PC/Desktop
CPU
i5-11400F
Motherboard
Gigabyte
Memory
32GB
Graphics Card(s)
Geforce GT-1030
Keyboard
Logitech K400
Mouse
Logitech M720
Internet Speed
600 Mb
Browser
Edge

My Computer My Computer

At a glance

W11 ProIntel(R) Core(TM) i7-477016GBIntel HD 4600 & GeForce GT 750M
OS
W11 Pro
Computer type
PC/Desktop
Manufacturer/Model
Dell XPS One 2720
CPU
Intel(R) Core(TM) i7-4770
Motherboard
Dell
Memory
16GB
Graphics Card(s)
Intel HD 4600 & GeForce GT 750M
Sound Card
Realtek HD Audio
Monitor(s) Displays
27"
Screen Resolution
2560*1440
Hard Drives
512GB SSD boot drive connected via mSATA card
2TB SSD Data Drive
Case
AIO
Internet Speed
1GB Fibre
Antivirus
Microsoft
from where to download complete genuine iso of this file, not from uup dump. it takes lot of time 4 hours in my case.
 

My Computer My Computer

At a glance

window 10 version 22H2 (OS Build 19045.6466Intel Core i7 @2.80GHz 57 °C Sandy Bridge 32n...4.00GB Dual-Channel DDR3 @ 665MHz (9-9-9-24)Intel HD Graphics 3000
OS
window 10 version 22H2 (OS Build 19045.6466
Computer type
Laptop
Manufacturer/Model
Dell/E6400
CPU
Intel Core i7 @2.80GHz 57 °C Sandy Bridge 32nm Tech
Motherboard
Dell Inc. 0K0DNP (CPU 1)
Memory
4.00GB Dual-Channel DDR3 @ 665MHz (9-9-9-24)
Graphics Card(s)
Intel HD Graphics 3000
Sound Card
High Definition Audio Device
Monitor(s) Displays
single
Screen Resolution
1366x768 pixels
Hard Drives
WDC WD2500BPVT-75JJ5T0
Keyboard
Device Name Standard PS/2 Keyboard
Mouse
PS/2 Compatible Mouse
Internet Speed
10mb
Browser
ms edge
Antivirus
win defender
Haven't I gotten any updates in a month? Is it because I locked everything down for privacy and security? All toggles in the settings are off, where applicable?!
 

My Computer My Computer

At a glance

Windows 11I don't knowIDKIntel
OS
Windows 11
Computer type
Laptop
Manufacturer/Model
HP
CPU
I don't know
Motherboard
IDK
Memory
IDK
Graphics Card(s)
Intel
Sound Card
?
Monitor(s) Displays
32 inches
Screen Resolution
IDK
Hard Drives
IDK
PSU
IDK
Case
HP
Cooling
?
Keyboard
Razer
Mouse
Razer
Internet Speed
Office
Browser
Windows 11
Antivirus
?
ISO from Microsoft:

 

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
 

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

Latest Support Threads

Back
Top Bottom