Overview
- Microsoft published the optional preview update KB5120998, which went live on Friday and makes new 26H2 code available to users who search for and install it via Windows Update.
- KB5120998 restores taskbar placement on all four screen edges and a smaller taskbar size and adds Start menu and File Explorer refinements that were long requested by users.
- The preview introduces Administrator Protection for stronger privilege separation, Microsoft Execution Containers (MXC) to sandbox agentic AI, and ML‑KEM as a standalone post‑quantum TLS key‑exchange option.
- Many PCs already contain 26H2 code that will be enabled gradually via small configuration files as an enablement package, a model that speeds activation but gives administrators control through Windows Update for Business and WSUS.
- Early installs of the preview have generated user reports of mouse cursor and wallpaper resets, third‑party tools like ViVeTool can force features early at support risk, and Windows 11 24H2 reaches end of support on October 13, 2026, raising upgrade urgency for enterprises and users.