Microsoft says recent Windows updates cause app install issues

Microsoft says the August 2025 security updates are triggering unexpected User Account Control prompts and app installation issues for non-admin users across all supported Windows versions, according to Windows release health dashboard update. The issue stems from a security patch addressing CVE-2025-50173, a Windows Installer privilege escalation vulnerability, which can allow authenticated attackers to gain SYSTEM privileges due to weak authentication.

Microsoft notes that new UAC prompts may appear in scenarios such as running MSI repair commands (for example msiexec /fu), installing applications that configure themselves for individual users, and when Windows Installer runs during Active Setup. The company lists a wide range of affected platforms, including client OSes such as Windows 11 versions 24H2, 23H2, and 22H2, Windows 10 versions 22H2, 21H2 and older LTSC builds, and server versions including Windows Server 2025, 2022, 2019, 2016, 2012 R2, and 2012.

As a temporary workaround, users are advised to run apps as administrator, or have IT admins apply Known Issue Rollback via Group Policy on specified Windows versions, while a fix is prepared and IT admins will be able to enable MSI repair operations without UAC prompts in future updates. There is also mention of another bug linked to the August 2025 updates affecting NDI streaming and Microsoft states there is no known connection to SSD/HDD reliability issues.