KB5121003


Microsoft has released cumulative update KB5121003 for Windows 11 version 25H2 (2025 Update) as part of the August 2026 Patch Tuesday. The update brings the build number to 26200.9168 and includes numerous File Explorer interface improvements, new touchpad gestures, expanded voice input support and a speech recognition system, an updated Windows Hello sign-in, as well as improved stability for DHCP, IPPS printing, and Office applications in virtualized environments. A separate addition is the ability to remove the AI image generation component on Copilot+ PCs.

Along with the listed new features, update KB5121003 addresses several known issues and introduces refinements to system components. A false Mark of the Web label for files from DFS drives and a File History automatic backup failure to SMB network folders have been fixed. The stability of Office applications in virtualized environments has been improved. Enhancements have been made to Widgets, Magnifier on touch screens, power and battery settings, Windows Update, Myanmar Text and Mongolian Baiti fonts, IPPS printing speed, and DHCP reliability. As part of the standard deployment, the range of devices automatically receiving new Secure Boot certificates has been expanded. Microsoft has added new data to more accurately determine target devices, increasing the scope of computers ready to automatically receive the new Secure Boot certificates. In the coming months, their phased rollout via Windows Update will continue on supported PCs and unmanaged corporate devices.

To install the update, open Settings, go to Windows Update, and click Check for updates. Cumulative update KB5121003 will be downloaded and installed automatically.

Feature / Change Performance Increase or Decrease Optimization PC Speed Gaming Optimization
File size display in appropriate units (KB, MB, GB) ⚪ No direct impact 🟢 High (instant readability, no manual calculation) ⚪ No impact ⚪ No impact
Open folders in new tabs via middle-click ⚪ No direct impact 🟢 Medium (reduces window clutter, faster multi-folder navigation) ⚪ No impact ⚪ No impact
Improved search relevance for apps and settings ⚪ No direct impact 🟢 High (faster result discovery, fewer mistyped queries) 🟢 Slight (reduces CPU time wasted on repeated searches) ⚪ No impact
Korean language support for Voice Access ⚪ No direct impact 🟡 Medium (hands-free navigation for Korean speakers) ⚪ No impact ⚪ No impact
Three speech recognition modes for noise filtering ⚪ No direct impact 🟢 High (more accurate dictation in noisy environments) ⚪ No impact 🟡 Low (background voice chat isolation may improve)
Adjustable touchpad scrolling speed and zoom sensitivity ⚪ No direct impact 🟢 Medium (personalized responsiveness, less frustration) ⚪ No impact ⚪ No impact
Touchpad accelerated scrolling feature ⚪ No direct impact 🟢 Medium (faster content traversal in long documents/pages) ⚪ No impact ⚪ No impact
Enhanced Sign-in Security (ESS) for external fingerprint scanners ⚪ No direct impact 🟢 High (quicker, secure login without typing PIN/password) ⚪ No impact ⚪ No impact
Subscription status icon in Start menu account manager ⚪ No direct impact 🟡 Low (glanceable account info, no need to open browser) ⚪ No impact ⚪ No impact
Ability to remove built-in AI image generation component 🟢 Slight increase (frees storage and background resource usage) 🟢 High (user control over pre-installed AI features, less clutter) 🟢 Slight (less disk I/O and memory consumption if removed) 🟢 Slight (more available system resources for gaming)

Find and Change Settings

Setting Where to find How to change
File Explorer: file size display and opening folders in new tabs File Explorer > View > Details
File Explorer > Address bar or Home
To see file sizes in appropriate units (KB, MB, GB), open File Explorer, switch to Details view using the View menu. To open a folder in a new tab, middle-click the folder in the address bar or the Home item.
Improved search for apps and settings Start menu > Search
Settings > Search
The relevance of search results is enhanced automatically. To search, open the Start menu or Settings and type your query. No additional configuration is required to benefit from the improved relevance.
Voice access and Voice Isolation Settings > Accessibility > Speech To add Korean language support, go to Settings > Accessibility > Speech and download the Korean language pack. To enable Voice Isolation and choose a speech recognition mode for better noise filtering, select one of the three available modes under the Voice access settings.
New touchpad gesture settings Settings > Bluetooth & devices > Touchpad To adjust scrolling speed or zoom sensitivity, open Settings > Bluetooth & devices > Touchpad and use the sliders. To enable accelerated scrolling, turn on the corresponding toggle in the same menu.
Enhanced Sign-in Security (ESS) for Windows Hello Settings > Accounts > Sign-in options To use an external fingerprint scanner for heightened security, plug in the device, then go to Settings > Accounts > Sign-in options, select Fingerprint recognition (Windows Hello), and follow the setup instructions.
Updated account manager in the Start menu Start menu > User icon The subscription status icon appears automatically next to your user name. To view quick account information, click your user icon in the Start menu.
AI component removal on Copilot+ PCs Settings > Apps > Installed apps To remove the built-in AI image generation component, go to Settings > Apps > Installed apps, locate the component in the list, click the three-dot menu, and select Uninstall.

Official announcement on the Microsoft website.

The last 10 Windows updates:

Update Build Version Windows Channel Date
KB5120996 28000.2796 26H1 Windows 11 Preview 2026-08-14
KB5120998 26200.9267 25H2 Windows 11 Preview 2026-08-14
KB5120240 22631.7517 23H2 Windows 11 Stable 2026-08-11
KB5120249 19045.7663 22H2 (ESU) Windows 10 Stable 2026-08-11
KB5121000 28000.2704 26H1 Windows 11 Stable 2026-08-11
KB5121003 26200.9168 25H2 Windows 11 Stable 2026-08-11
KB5101677 28020.2623 26H1 Windows 11 Beta 2026-07-31
KB5101680 28120.2630 26H1 Windows 11 Experimental 2026-07-31
KB5101683 26220.9022 25H2 Windows 11 Beta 2026-07-31
KB5101682 26300.9032 26H2 Windows 11 Experimental 2026-07-31