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 told CNET, "We are actively working on mitigations and recommend customers track the latest known issues through the Windows Release Health dashboard ."
According to the dashboard, most of the issues for the 24H2 update
have been resolved, and for the 25H2 update
, the mouse and keyboard issue has been resolved. The locally hosted apps issue is still being worked on, according to the status update page
.
Microsoft provided CNET links to a page on an initial fix for Windows 11 updates
and a link for Windows 2025 server updates
.
The update issue comes at a critical time for Microsoft: Last week, the company ended official support for Windows 10 .
Temporary solutions
The website Windows Latest previously said it was communicating with Microsoft about the update bugs and that a hotfix could take several days. The original updates were issued on Oct. 14.
"Microsoft told me that affected users should check for updates and reboot their PC, even if they do not see any newer updates listed," Mayank Parmar wrote in a Windows Latest post .
That process, Parmar wrote, allows Windows to roll back its code once that fix is available. The website also offered a modification to Windows Registry that could temporarily address the ability for local apps to use networking and other workarounds and fixes for the issues the update has caused.
