Just two days after the conclusion of support for Windows 10, a wave of complications has emerged with Microsoft’s latest Windows 11 October update. Users across various platforms, including Microsoft Support Forums, Stack Overflow, and Server Fault, have reported that the localhost functionality in Windows 11 is currently non-operational. This disruption is particularly detrimental to millions of web developers who rely on their PCs to run applications locally.
Impact of the October Update
The update in question, KB5066835, was intended to bolster security and enhance the quality improvements introduced in the September update, KB5065789. However, it inadvertently compromised the localhost function—a virtual hostname that enables a PC to act as its own server. This feature is essential for local developers who need to test websites or fully developed web applications. The ramifications of this disruption are profound, affecting developers who utilize Windows 11 on their local servers or workstations for production tasks.
As the diligent team at Microsoft continues to investigate, the community has found a workaround: uninstalling the October KB5066835 package, and if necessary, the September KB5065789 package as well. Reports from software engineers indicate connection failures and issues with the HTTP/2 protocol, which are impacting various development tools, including ASP.NET compilation processes and Visual Studio debugging functionalities.
Further investigation has traced the root of the problem back to build version 26100.6899, pinpointing HTTP.sys—a kernel-level component responsible for managing HTTP traffic on local systems—as the source of the issue. This growing stack of complications surrounding Microsoft’s latest Windows 11 release raises concerns about the platform’s reliability.
In a series of missteps, Microsoft also encountered an accidental disruption of the Windows Media Creation Tool (MCT) just one day before Windows 10’s end-of-life announcement. Additionally, the company has begun enforcing Online Accounts for Windows 11 installations, a move that many users find increasingly difficult to bypass. The ongoing stream of broken functionalities prompts a critical question: will users remain loyal to the Windows operating system, or will they seek alternatives as these issues continue to mount?
