Microsoft has released cumulative preview update KB5120998 for Windows 11 versions 25H2 and 24H2, which contains 35 changes including improvements to the Start menu, taskbar and Windows Search.
KB5120998 is a preview update that allows IT administrators to test Windows bug fixes, improvements, and new features before they are rolled out to all users during next month’s Patch Tuesday release.
However, unlike cumulative updates, monthly optional updates do not contain security fixes and only provide quality improvements.
After installing the August 2026 Preview Update, users can move the taskbar to the bottom, top, left, or right of the screen in Settings > Personalization > Taskbar > Taskbar Behavior > Taskbar Position, with most customization settings, such as: E.g. no combination of taskbar icons will work in any position.
The KB5120998 also adds a new smaller taskbar option that reduces the taskbar height and size of taskbar icons to maximize screen space on smaller devices, as well as small or large size options for the Start menu (in Settings > Personalization > Taskbar > Taskbar Behavior > Taskbar Size dialog), as well as the ability to independently show or hide the Pinned, Featured, and All sections and the account name and the Hide profile picture.
With KB5120998, Microsoft also began rolling out the Administrator Protection security feature, which allows users to perform administrative tasks using just-in-time permissions.
“Admin protection is not classified as a formal security boundary; it increases security against elevation-of-privilege attacks by introducing profile separation,” Microsoft said. “This feature is disabled by default and can be enabled using OMA URI in Microsoft Intune or through Group Policy.”
You can install KB5120998 by opening it Windows Settingsclick on Windows Update, and then click “Check for updates.”.’
Since this is an optional update, you must click the “Download and install” link unless you have already checked the “Get the latest updates as soon as they are available” option, which will prompt the operating system to install them automatically.
You can also manually download and install the KB5120998 preview update from Microsoft Update Catalog.
Windows 11 Highlights KB5120998
Once installed, this optional, non-security update updates Windows 11 25H2 and 24H2 devices to builds 26200.9278 and 26100.9278, respectively.
The August 2026 Preview Update brings many other changes, some of which are highlighted below:
- Windows will now automatically index your most frequently used folders so that these files appear in subsequent search results. You can control the setting in Settings > Privacy & Security > Search > Find more relevant places automatically.
- This update improves reboot behavior so that PCs that were manually put to sleep will go back to sleep after an update is complete, even if auto-sleep is set to Never.
- This update adds support for participating apps to coordinate their updates with Windows Update. Supported apps can benefit from improved scheduling and a streamlined update experience. For more information, see Windows Update Orchestration Platform (UOP).
- This update improves resiliency and recovery from potential background issues related to VPN processes that can cause processes to stop responding.
- Starting August 2026, Windows 11 versions 24H2 and 25H2 will no longer include the Windows Management Instrumentation Command-line (WMIC) utility. WMIC is already removed by default in new installations of Windows 11 versions 24H2 and 25H2 and will no longer be available as a Feature on Demand (FoD).
On Thursday, Microsoft warned customers that their systems may reboot again after deploying the optional August 2026 update and rolling out updates over the next few months.
“Due to recent and upcoming Windows updates in the next few months, a limited number of consumer and business devices may experience an additional reboot during installation.” Microsoft noted in a message center update. “This one-time reboot occurs after a Secure Boot certificate update is applied as part of the Secure Boot update process.”
Earlier this month, customers were also reminded that devices running the Home and Pro editions of Windows 11 24H2 will stop receiving updates in two months. However, the Windows 11 24H2 Enterprise and Education editions will remain in mainstream support until October 2027.
Users are recommended to update to Windows 11 25H2 (also known as Windows 11 2025 Update), which became generally available in September 2024.
Overall prevention scores can hide what happens after the first access. Once attackers use valid credentials, prevention drops sharply.
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