Windows 11 KB5079391 Update Brings Smart App Control and Display Improvements

Microsoft has released a new Windows 11 preview update, KB5079391, covering both the 24H2 and 25H2 branches. The package delivers 29 changes focused on enhancing Smart App Control and various display reliability improvements, reflecting Microsoft’s ongoing testing of features ahead of the next Patch Tuesday. This preview is part of the company’s monthly non-security preview cadence and is optional; unlike regular Patch Tuesday updates, it does not include security fixes.

A key change in this March 2026 preview is the ability to configure Smart App Control (SAC) without a clean OS reinstall. Users can adjust SAC settings by going to Settings > Windows Security > App & Browser Control > Smart App Control settings. When SAC is enabled, the feature helps block untrusted or potentially harmful applications, and the new approach makes it simpler to tailor protection to individual systems without performing a full OS reset.

In addition to SAC, the update brings a series of display-related reliability improvements. Notable items include support for monitors reporting refresh rates higher than 1000 Hz, better native USB4 monitor connections, and improved high dynamic range (HDR) reliability. These tweaks are part of the ongoing effort to stabilize visual performance across a wider range of display hardware.

For installation, users can obtain KB5079391 through the Microsoft Update Catalog or by opening Settings, selecting Windows Update, and choosing “Check for Updates.” Since this is an optional preview, you’ll typically see a prompt to download and install, unless your device is configured to install updates automatically as soon as they’re available.

When installed, the March 2026 preview updates will upgrade devices running Windows 11 25H2 and 24H2 to builds 26200.8116 and 26100.8116, respectively. Among the improvements highlighted in this release are:

• Performance & Reliability: Stability improvements in the Windows Recovery Environment (Windows RE) when running 64-bit applications on ARM64 devices, resulting in smoother operation and better responsiveness for those apps.
• Update Download Reliability: Enhanced reliability for downloading required updates when prompted within Settings > System > Advanced.
• Windows Hello: Increased reliability of Windows Hello Fingerprint on certain devices, contributing to quicker and more dependable authentication.
• Settings Dialog Design: A refreshed look for the dialog boxes in Settings > Accounts > Other users to align with the modern Windows aesthetic and to support dark mode. The visibility of these options can depend on whether the device is tied to a domain-joined work or school account.

Microsoft notes that there are no known issues currently associated with this update, and the full release notes can be found in the relevant support bulletin. The KB5079391 preview continues the pattern set by earlier previews, such as KB5077241, which introduced improvements to BitLocker, Sysmon functionality, and a new network speed test tool.

In summary, the KB5079391 preview for Windows 11 24H2 and 25H2 brings practical enhancements to Smart App Control configurability and display reliability, along with several targeted reliability and usability improvements. As with other monthly previews, it serves as a testing ground for features that may become part of the next Patch Tuesday rollout, emphasizing optional installation and user control over enabling new capabilities.