Microsoft Confirms UAC Bug Disrupts App Installation on Windows 10 & 11

Microsoft has officially acknowledged a significant User Account Control (UAC) bug that is causing widespread installation issues across Windows 10 and Windows 11 systems.

The problem stems from a security update released in August 2025 and affects millions of users attempting to install or repair applications.

The Core Issue

The bug emerged following Microsoft’s August 2025 Windows security update (KB5063878), which introduced enhanced security measures to address vulnerability CVE-2025-50173.

While the update successfully patched a critical security flaw, it inadvertently created a new problem for standard users trying to perform routine software operations.

Users now encounter unexpected UAC prompts demanding administrator credentials when running Windows Installer (MSI) repair operations.

This affects popular applications including Autodesk AutoCAD, Civil 3D, Inventor CAM, and Microsoft Office Professional Plus 2010.

What Users Are Experiencing

The most common scenarios triggering these problematic UAC prompts include:

• Running MSI repair commands
• Launching Autodesk applications for the ...