Overview
- Microsoft published the optional preview update KB5120998 on Friday, August 28, 2026, which surfaces taskbar repositioning to all four screen edges, a compact taskbar size and new Start and search settings while warning many features will roll out gradually after install.
- Administrator Protection is introduced to change how elevation works by asking users to approve requests and running approved apps in a separate derived admin account to limit privilege exposure.
- Microsoft Execution Containers (MXC) are added to sandbox agentive AI processes and Windows now offers the post‑quantum ML‑KEM algorithm as a standalone option for TLS key exchange.
- Windows 11 26H2 has been promoted to the Release Preview channel as an Enablement Package that unlocks features via small configuration files, and Microsoft signals a wider October rollout with Windows 11 24H2 Home and Pro reaching end of support on October 13, 2026.
- Enterprises and users should plan tests and deployment controls because some features will be present but disabled by configuration, WMIC is being removed, and sandbox technologies like MXC will need operational validation to prove containment works in practice.