Windows 10 KB5066791 Update
Windows 10 KB5066791 is the last update for users without Extended Security Updates (ESU) subscription.
This update patches several bugs, mainly focused on enterprise changes, and is available via Windows Update or direct download links (.msu).
Upon installation, no visible changes were observed, with the update showing as "2025-10 Cumulative Update for Windows 10 Version 22H2 for x64-based Systems (KB5066791)".
Microsoft prompts users to sign up for Extended Security Updates but does not explicitly warn that this is the last update.
The October 2025 Update advances PCs to Windows 10 Build 19045.6456, with tests revealing full-screen nudges to upgrade to Windows 11.
Windows 10 KB5066791 is the last update if you don’t subscribe to ESU.
Author's summary: Last Windows 10 update without ESU subscription.