KB5065428: [Input and Composition] Fixed

September 9, 2025—KB5065428 (OS Build 17763.7792)

This security update includes fixes and quality improvements that are part of the following update:

• ​​​​August 12, 2025—KB5063877 (OS Build 17763.7678)
• August 19, 2025—KB5066187 (OS Build 17763.7683) Out-of-band

The following is a summary of the issues that this update addresses when you install this update. The bold text within the brackets indicates the item or area of the change we are documenting.

• [Input and Composition] Fixed: An issue with the Chinese Simplified Input Method Editor (IME). Some extended characters were showing as empty boxes.
• [App compatibility (known issue)] Fixed: Addresses an issue that caused non-admin users to receive unexpected User Account Control (UAC) prompts when MSI installers perform certain custom actions. These actions might include configuration or repair operations in the foreground or background, during the initial installation of an application.

This issue could prevent non-admin users from running apps that perform MSI repairs, including Office Professional Plus 2010 and multiple applications from Autodesk (including AutoCAD). This fix reduces the scope for requiring UAC prompts for MSI repairs and enables IT admins to disable UAC prompts for specific apps by adding them to an allowlist. For more information, see Unexpected UAC prompts when running MSI repair operations after installing the August 2025 Windows security update.

• [File Server] New! This update enables auditing SMB client compatibility for SMB Server signing as well as SMB Server EPA. This allows customers to assess their environment and identify any potential device or software incompatibility issues before deploying the hardening measures that are already supported by SMB Server. For detailed guidance, see CVE-2025-55234 | Windows SMB Elevation of Privilege Vulnerability.