Win11 Security Patch Disables USB, Recovery Tools
Microsoft is working to address multiple serious bugs introduced by its October, 2025 security update for Windows 11 (dubbed KB5066835), which has left users unable to fix their computers when problems occur. The bug disables many keyboards and mice at the worst possible moment.
The most critical issue affects the Windows Recovery Environment, a built-in troubleshooting tool that automatically appears when a computer fails to start normally. After installing the update, USB keyboards and mice stop working entirely in this repair mode, leaving affected users with no way to click buttons or select options to fix their computers. The problem only occurs in the recovery environment itself, with USB devices functioning normally when Windows is running properly.
Software Developers Also Affected
The same update also broke a feature called "localhost" (i.e., the IP address 127.0.0.1 which pings back to the same machine). This IP is used when software developers need to test websites and applications on their own computers before publishing them online with a real IP address. Localhost essentially allows a computer to act as its own private web server for testing purposes.
The bug prevents these local test sites from loading, forcing many developers to uninstall the problematic update to continue their work. Some have found temporary workarounds that involve changing technical settings, though these solutions are far from ideal. (Source: theregister.com)
Fix Coming Soon
Microsoft has acknowledged the problems and stated that engineers are developing fixes. Other issues identified include problems with security card authentication, installation failures for certain updates, and some business applications failing to load properly. (Source: theregister.com)
The timing proves particularly awkward for Microsoft, as the company officially ended Windows 10 support this month and has been actively encouraging users to upgrade to Windows 11. The operating system, released in 2021, is used by almost half of Windows users, while Windows 10 still accounts for 40 percent despite losing official support.
What's Your Opinion?
Does the frequency of bugs in Windows updates concern you about the overall quality control at Microsoft? Is it reasonable to expect Microsoft's testing to pick up these specific bugs? Have you experienced any problems with the October Windows 11 update, and if so, how did you resolve them?
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Comments
AI?
You have to wonder how much of the code was written by AI since Microsoft said they’re using AI to write code.
Not affected by Windows 11 updates as I chose to stay with Windows 10.
October Win 11 update
M$ sent out a fix for this a few days ago. I believe it
is KB5070773 (21600.6901).
Correct - USB fix
On this page:
https://support.microsoft.com/en-us/topic/october-20-2025-kb5070773-os-builds-26200-6901-and-26100-6901-out-of-band-0f533ed7-949a-4b89-8d0f-6ee751adfcd4
It says it fixes the USB portion of the bugs, but doesn't say anything about the localhost issue. I did test the localhost on my own machine and it doesn't seem to be affecting me.