Windows 11 Update: KB5074109 Fixes Critical AVD and Gaming Bugs

Microsoft recently rolled out Windows 11 Update KB5074109, released in January 2026. This cumulative update brings significant enhancements, particularly focusing on security and device efficiency. However, it has also introduced critical bugs impacting both professional and gaming experiences.

Key Improvements in Update KB5074109

This update targets Windows 11 versions 24H2 and 25H2, and includes the following key improvements:

• Massive Security Patch: This update addresses 114 security vulnerabilities, significantly enhancing system safety.
• Enhanced Battery Life: A flaw causing Neural Processing Units (NPUs) to stay active during idle states has been resolved, improving battery performance on modern laptops.
• File Explorer Upgrades: The homepage now features a “Recommended” section, displaying frequently used or downloaded files. Users must have a Microsoft account to access this feature. The Dark Mode consistency has also been improved.
• Expanded QR Code Sharing: Users can now generate QR codes for website links, cloud files, and mobile hotspots directly from the share window.
• Usability Tweaks: The Start Menu includes a new account manager and enables drag-and-drop functionality for apps on the taskbar.

Critical Issues and Reported Bugs

Despite these improvements, users have encountered several serious issues:

• AUD Failure: Azure Virtual Desktop users are experiencing fatal authentication errors (code 0x8008005), halting their workflows. Currently, the only workaround is uninstalling the update.
• Gaming Performance Drops: Users, especially those using NVIDIA graphics cards, have reported decreases in gaming performance, with frame rates dropping by around 20 FPS.
• USB Formatting Bug: There are reports of Windows failing to format USB drives formatted with the FAT32 file system.

Should You Install This Update?

Deciding whether to install KB5074109 depends on your user profile:

• General Users: For standard home users focused on security, installing this update is advisable due to the significant number of vulnerabilities addressed.
• Professionals and Gamers: If your work relies on Azure Virtual Desktop or if you are an avid gamer, it is recommended to avoid this update. Wait for a follow-up patch from Microsoft that resolves these critical bugs.

System Build Number Changes

After installing the update, the OS build numbers will change as follows:

In conclusion, the KB5074109 update for Windows 11 offers vital security enhancements while also presenting some significant challenges. It is essential for users to weigh the benefits against potential drawbacks before proceeding with the installation.