HTTP/2 Archives

Winsage

October 26, 2025

“Emergency Windows Update Declared a ‘Total Disaster’—Is Your PC at Risk?”

A new Windows 11 update, KB5066835, is causing significant issues by breaking localhost connections, preventing locally hosted apps from communicating with the network. Users are experiencing installation failures and problems with peripherals and accessories. Microsoft has acknowledged the issue and is rolling out an emergency patch, which may take over 48 hours to reach affected PCs. The update disrupts the kernel-mode HTTP server (HTTP.sys), leading to connection failures for apps trying to access localhost. Additionally, the update renders the Windows Recovery Environment (WinRE) unusable, as mice and keyboards do not function within it. Users attempting to reinstall the patch or upgrade to newer builds have reported inconsistent results, with fresh installs of Windows 11 24H2 not experiencing the same issues. Caution is advised against attempting unofficial fixes, as they may destabilize the system. Windows 10 users should ensure their systems are updated with the final security patches or consider purchasing Extended Security Updates for continued support.

Winsage

October 21, 2025

Microsoft to release emergency fix for recent Windows 11 update

Microsoft is preparing to release an emergency update in response to significant disruptions caused by the recent Windows 11 update, KB5066835, which introduced critical bugs affecting many devices. Users have reported issues such as failure in localhost HTTP/2 connections, inability for locally hosted applications to connect to the network, malfunctioning Logitech hardware, non-responsive mouse and keyboard in the Windows Recovery Environment, and File Explorer documents failing to open in the Preview pane due to a false security alert. Microsoft is working on a patch and advises users to check for updates, which may take up to 48 hours to be available to all. Windows 11 now holds nearly 50% of the market share, while Windows 10, which is unsupported, has a 40% market share.

Winsage

October 20, 2025

Microsoft fixes Windows Server Active Directory sync issues

Microsoft is addressing an issue with Active Directory functionalities for certain Windows Server 2025 systems after the installation of the September 2025 security update (KB5065426). The problem affects applications using Active Directory directory synchronization (DirSync), particularly for large security groups exceeding 10,000 members, resulting in incomplete synchronization. To resolve this, IT administrators can implement the Known Issue Rollback (KIR) Group Policy on affected devices. For non-managed devices, a temporary fix involves adding a registry key at the specified path with a specific name, type, and value. Additionally, Microsoft is working on resolving a bug affecting Windows updates on Windows 11 24H2 and Windows Server 2025, as well as addressing smart card authentication issues and HTTP/2 localhost connection disruptions following recent security updates.

Winsage

October 19, 2025

Microsoft Confirms Emergency Update For Millions Of Windows Users

Microsoft's latest mandatory security update for Windows 11, KB5066835, has caused significant disruptions, including inoperable localhost connections and multiple installation failures. Users are experiencing issues with locally hosted applications, and the update has also affected certain Logitech peripherals and mouse and keyboard functionality in the Windows Recovery Environment (WinRE). Microsoft has acknowledged these problems and plans to release an emergency fix within 48 hours. A regression in the kernel-mode HTTP server (HTTP.sys) is responsible for the localhost connectivity issues, particularly impacting Internet Information Services (IIS). Users are advised against seeking online troubleshooting solutions, as they have proven ineffective, and some have found risky temporary workarounds.

Winsage

October 18, 2025

Microsoft fixes Windows bug breaking localhost HTTP connections

Microsoft has identified a bug affecting HTTP/2 localhost connections and IIS websites after recent Windows security updates, specifically the Windows 11 KB5066835 Patch Tuesday update and the September KB5065789 preview update. Users have reported connection reset errors, such as ERRCONNECTIONRESET and ERRHTTP2PROTOCOL_ERROR, impacting applications like the Duo Desktop app and Visual Studio debugging. The issue is linked to a bug in the HTTP.sys web server used by ASP.NET Core, which can be triggered by various factors including device restarts and update installations. Microsoft has provided steps for resolution, including checking for updates and restarting devices. For non-managed devices, an automatic resolution through Known Issue Rollback (KIR) is available, while enterprise-managed devices require IT administrators to implement KIR group policies. A permanent fix is expected in a future Windows update.