Microsoft warns USB mouse keyboard users as Windows 11 KB5066835 breaks key OS feature

Microsoft released the first Patch Tuesday update (KB5066835) for Windows 11 25H2 this past week and it is probably fair to say that it has been a rough start for the new feature update. Despite the announcement of a wide rollout wherein the new version is now available for download for everyone, the company has already confirmed large-scale issues.

First up, Microsoft was forced to issue an emergency workaround as the update broke localhost auth and following that the company today has confirmed another problem where recovery can become impossible if you happen to use a USB keyboard or mouse.

The company has confirmed that following the installation of the latest Patch Tuesday update USB keyboard and mouse inputs no longer register inside the WinRE (Windows Recovery Environment). Thus if you happen to get stuck in recovery and use such a device you will be out of luck.

Microsoft did publish new Recovery updates this week alongside Patch Tuesday under KB5067039 and KB5067019, though the company does not specify anything about this issue in its release notes.

On the issue description, Microsoft writes: "After installing the Windows security update released on October 14, 2025 (KB5066835), USB devices, such as keyboards and mice, do not function in the Windows Recovery Environment (WinRE). This issue prevents navigation of any of the recovery options within WinRE. Note that the USB keyboard and mouse continue to work normally within the Windows operating system."

This is potentially a really big problem considering the WinRE provides various key OS recovery functions like troubleshooting, Reset, Startup Repair, Command Prompt, and more, that can be essential to help troubleshoot and repair unbootable systems.

Also, most users nowadays probably rely on USB-based inputs. PS/2 ports can still sometimes be present on motherboards but getting a PS/2 mouse or keyboard can become a problem as they can be scarce in many regions of the world. Bluetooth mouse without a USB dongle may not work inside WinRE either.

Right now the company says that it is working on a fix as it investigates the issue. Ironically Microsoft's new "Hey Copilot" voice input feature—that is hoped to replace mice and keyboards entirely someday—would also prove useless here as it does not work outside the OS.

Source

Hope you enjoyed this news post. Feedback welcome.

Posted Sunday 19 October 2025 at 4:52 am AEST (my time).

News posts... 2023: 5,800+ | 2024: 5,700+ | 2025 (till end of September): 4,533

RIP Matrix