The latest Windows 11 24H2 and 25H2 updates cause IIS (Internet Information Services) websites to malfunction due to a conflict in the HTTP.sys driver.
Impact on IIS Websites
Microsoft acknowledged that the updates, released on or after 2023-09-29, lead to "ERR_CONNECTION_RESET" errors, impacting devices using IIS. This issue arises primarily in environments using localhost loopbacks or relying on HTTP.sys for incoming connections.
The problem particularly affects server-side applications, resulting in failed connections and blank pages, which could disrupt developer environments reliant on this setup.
Temporary Solution and Workaround
To address the issue, Microsoft recommends a Known Issue Rollback (KIR) via a special Group Policy configuration. This rollback allows users to revert the problematic changes without removing the entire update.
- The rollback can be configured in Computer Configuration > Administrative Templates.
- Microsoft is actively working on a permanent resolution.
- The company has also removed an upgrade block affecting installations of Windows 11 24H2.
IT administrators are encouraged to apply this workaround to restore system functionality while awaiting a permanent fix.
