A mandatory Windows 11 security update is wreaking havoc on some systems, and Microsoft is working on a hotfix to reverse the damage. Several Windows- and tech-focused websites report issues with Windows 11 KB5066835 . The sites report that the update can disable mice and keyboards in recovery mode, disable network connections for locally hosted apps and cause issues with previewing files in Windows Explorer.

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The update, for Windows 11 versions 24H2 and 25H2 as well as Windows Server 2025, was automatically installed on some systems and could render PCs unusable.

A representative for Microsoft did not immediately respond to a request for comment.

Temporary solutions

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