The August 2025 Windows security updates introduced several changes and improvements aimed at enhancing system security and performance. However, these updates also led to notable issues affecting users who rely on specific software and hardware functionalities. Two primary concerns emerged: performance degradation in NDI (Network Device Interface) streaming and unexpected User Account Control (UAC) prompts during MSI (Microsoft Installer) operations. These issues impacted a wide range of applications, including streaming tools like OBS Studio and enterprise software such as AutoCAD. Microsoft and third-party developers provided workarounds and resolutions, with some issues being addressed in subsequent updates. This article explores the nature of these problems, the affected platforms, and the available solutions, based solely on the information provided in the source documentation.
NDI Streaming Performance Issues After August 2025 Update
A significant concern following the August 2025 Windows security update was the degradation of NDI streaming performance. Users who rely on NDI for transferring audio and video feeds between devices reported experiencing severe stuttering, lag, and choppy playback. This issue was particularly noticeable when using streaming applications such as OBS Studio (Open Broadcaster Software) and NDI Tools. The problem was not confined to high-bandwidth scenarios; even under low-bandwidth conditions, users encountered similar performance issues. This degradation was attributed to the update’s impact on the Network Device Interface and its interaction with system resources.
The issue was traced back to the August 2025 Windows security update (KB5063709), which introduced changes that inadvertently affected NDI’s real-time communication protocols. The problem was further compounded when the "Display Capture" feature was enabled on the source PC, a common configuration in streaming workflows. The issue was not limited to a specific version of NDI but affected all users who had installed the August 2025 update and used NDI for streaming or transferring media.
Microsoft acknowledged the problem and released a resolution in the form of the September 2025 Windows update (KB5065429). This update addressed the underlying cause of the performance degradation and restored normal NDI functionality. According to Microsoft’s documentation, users who installed KB5065429 or later updates no longer needed to apply any workarounds for the issue. For users who had not yet upgraded to the September 2025 update, a manual workaround was available. This involved changing the NDI Receive Mode to use TCP or UDP instead of RUDP, which was the default protocol. This workaround allowed users to mitigate the issue until they could install the latest update.
The affected platforms included a wide range of Windows versions, from Windows 10 (22H2 and 21H2) to Windows 11 (24H2). The issue was exclusive to client devices and did not affect server platforms. This distinction was important for enterprise users who managed both client and server environments, as it allowed them to focus their mitigation efforts on the affected client systems.
UAC Prompts for MSI Repair Operations
Another notable issue introduced by the August 2025 Windows update involved changes to the behavior of User Account Control (UAC) prompts during MSI (Microsoft Installer) repair operations. The update included a security improvement that enforced the requirement for administrator credentials when performing certain MSI-related tasks, such as repairs and installations. This change was implemented to address the security vulnerability identified as CVE-2025-50173. While this enhancement improved system security, it also led to unexpected UAC prompts for standard users in various scenarios.
The most common situations where users encountered UAC prompts included running MSI repair commands (such as msiexec /fu), opening certain Autodesk applications (including AutoCAD, Civil 3D, and Inventor CAM), and installing apps that configured user-specific settings. Additionally, users experienced UAC prompts during Windows Installer operations in Active Setup and when deploying packages via Configuration Manager (ConfigMgr) that relied on user-specific configurations. The issue also affected scenarios involving the enabling of Secure Desktop.
For IT administrators, this change posed a challenge, as it disrupted automated deployment workflows and required manual intervention to approve UAC prompts. Microsoft provided a workaround for this issue, allowing IT administrators to disable UAC prompts for specific MSI files by adding them to an allowlist. This workaround was detailed in the KB article related to the issue and was made available to help organizations manage the transition period.
The resolution to this issue was included in the September 2025 Windows update (KB5065429), which refined the behavior of UAC prompts during MSI repair operations. According to the update notes, UAC prompts would now only be required if the target MSI file contained an elevated custom action. This change significantly reduced the number of unexpected prompts for standard users while still maintaining the security benefits of the original update.
The affected platforms for this issue were extensive, covering multiple versions of Windows 10 and Windows 11, including the Long-Term Servicing Channel (LTSC) and Enterprise LTSB editions. Server platforms were also affected, with the issue impacting Windows Server 2025, Windows Server 2022, and several older versions such as Windows Server 2016 and 2012 R2. This broad reach highlighted the importance of the resolution for both enterprise and end-user environments.
Resolution and Rollback Considerations
Both the NDI streaming performance issue and the UAC prompt behavior were addressed in the September 2025 Windows update (KB5065429). For users who had not yet applied this update, Microsoft provided a Known Issue Rollback (KIR) Group Policy to mitigate the NDI performance problem. This Group Policy allowed organizations to temporarily revert to a previous system configuration until the September update could be deployed. However, once KB5065429 was installed, the need for the KIR Group Policy was eliminated, and users could rely on the update to resolve the issue.
For the UAC prompt issue, Microsoft offered a similar approach by providing a workaround that allowed IT administrators to disable prompts for specific MSI files. This workaround was detailed in the KB article and was designed to help organizations manage the transition period before the September update was applied. Once the update was installed, the need for this workaround was no longer necessary, as the update refined the behavior of UAC prompts during MSI operations.
Microsoft also emphasized the importance of installing the latest Windows updates to ensure that users and organizations were protected against security vulnerabilities and received performance improvements. The company recommended that users check for and install the latest updates regularly, especially when dealing with critical system functions such as security, installation, and streaming.
Implications for Users and IT Administrators
The August 2025 Windows updates had significant implications for both end users and IT administrators. For end users, the changes to NDI streaming performance and UAC prompts disrupted common workflows, particularly for those involved in video production, broadcasting, and software deployment. The need to manually adjust settings or install updates added an extra layer of complexity to these tasks. However, the availability of workarounds and the subsequent resolution in the September update provided a clear path for users to mitigate these issues.
For IT administrators, the challenges were more pronounced, as the issues affected automated deployment processes and required manual intervention. The UAC prompt changes, in particular, disrupted Configuration Manager deployments and other enterprise software management tools. The workaround involving the allowlist for MSI files allowed administrators to maintain control over the deployment process while waiting for the September update. This flexibility was crucial for organizations that needed to maintain operational continuity without compromising security.
The broader implications of these updates also highlighted the importance of staying current with system updates. While the August 2025 updates introduced some unintended side effects, they also included important security improvements. The resolution provided by the September update demonstrated Microsoft’s commitment to addressing user concerns while maintaining system security.
Conclusion
The August 2025 Windows security updates introduced notable issues affecting NDI streaming performance and UAC prompts during MSI operations. These issues impacted a wide range of applications and workflows, particularly for users involved in video production and enterprise software deployment. Microsoft addressed both problems through the September 2025 update (KB5065429), which resolved the underlying causes and restored normal functionality. For users who had not yet installed this update, workarounds were available to mitigate the issues until the update could be applied.
For both end users and IT administrators, the experience underscored the importance of staying current with system updates while being prepared to address unexpected changes. The resolution of these issues in the September update demonstrated Microsoft’s responsiveness to user feedback and its commitment to maintaining system stability and security. As the software ecosystem continues to evolve, users and organizations must remain vigilant in monitoring and adapting to new updates to ensure smooth and secure operations.