Microsoft has acknowledged that the recent Windows 11 24H2 and 25H2 updates are causing disruptions for IIS (Internet Information Services) websites, a situation that arose following the October Patch Tuesday release. The root of the issue lies in a conflict within the Windows HTTP stack driver (HTTP.sys), which results in users encountering “ERRCONNECTIONRESET” errors when attempting to access localhost loopbacks or other IIS-based connections.
Impact on Users and Environments
The problem is particularly affecting devices that have installed updates released on or after September 29, including KB5066835 and KB5065789. According to Microsoft’s update on the Windows Release Health Dashboard, “server-side applications relying on HTTP.sys may experience issues with incoming connections,” leading to failed IIS websites or blank pages. This bug notably impacts localhost setups and developer environments, creating hurdles for those engaged in internal testing and web app hosting.
Microsoft has indicated that the issue may manifest under various conditions, such as differences in internet connectivity, system timing, or the order in which updates are installed. Consequently, not every Windows environment will be affected uniformly, but for those that are, the disruption can be significant.
Proposed Solutions
While the tech giant is actively working towards a permanent resolution, IT administrators have been advised to implement a known issue rollback (KIR) through a specific Group Policy configuration. This rollback serves to restore system stability by reversing the problematic changes without necessitating a complete uninstallation of the update.
For those managing Windows 11 24H2, 25H2, and Windows Server 2025, Microsoft has provided a dedicated download link. The Group Policy package can be located under Computer Configuration > Administrative Templates following installation.
In a more positive development, Microsoft has also lifted an upgrade block on Windows 11 24H2 devices, which had previously been in place due to a conflict with a third-party driver that was hindering installations.
