Microsoft has responded to a serious problem with Windows 11, where installing update KB5066835 can break USB keyboards and mice, preventing them from working in the Windows Recovery Environment (WinRE) and leaving you unable to do anything.
As of yesterday, Microsoft has released two emergency out-of-band updates to address the issue: KB5070762 and KB5070773, which are both for Windows 11 24H2 and 25H2. Keep reading for more details on the underlying issue and these hotfixes.
USB input devices fail after update
The issue affects systems running Windows 11 version 24H2 or 25H2 as well as Windows Server 2025. After installing the October update (KB5066835), USB keyboards and mice and other input devices no longer work properly in the recovery environment. This meant users were no longer able to repair PCs or reset Windows.
The two updates that fix the issue
Microsoft confirmed the bug and quickly announced an emergency update to correct the faulty driver initialization issue.
- KB5070762 is the so-called Safe OS Dynamic Update, which directly repairs the WinRE components of Windows 11.
- KB5070773 is a supplementary cumulative update (Builds 26100.6901 and 26200.6901) which addresses the same bug on systems where the Safe OS update doesn’t take effect automatically.
Both updates address the same problem, ensuring that USB keyboards, mice, and dongles work again in the recovery environment. Microsoft emphasizes that no other changes are made to the system and no reboot is required with these updates.
The emergency updates are distributed automatically via Windows Update, but can also be downloaded manually from the Microsoft Update Catalog if needed (KB5070762 and KB5070773). Microsoft recommends that companies promptly install these updates to avoid possible support failures during system recovery.
