Security

Windows 11 KB5074109: 114 Fixes, AVD Failures, FPS Drops

Krishn patel

Krishn patel

— 2 min read
Windows 11 KB5074109: Patch or Wait?
Patch Alert

Key Takeaways:

  • KB5074109 patches 114 security vulnerabilities and improves NPU-related battery life.
  • New usability features arrive: File Explorer "Recommended" section, expanded QR sharing, and Start menu tweaks.
  • Critical bugs reported: Azure Virtual Desktop authentication failures (0x8008005), gaming FPS drops on NVIDIA GPUs, and USB FAT32 formatting errors.
  • If you rely on AVD or are a serious gamer, delay this update; home users should prioritize the security fixes.

Overview

Microsoft released KB5074109 as the January 2026 cumulative update for Windows 11 (24H2 and 25H2). The package focuses on security, battery efficiency for NPU-equipped devices, and several usability improvements. While it closes a large set of vulnerabilities, some newly introduced bugs are severe for specific workflows.

What the Update Fixes and Adds

Security and Battery

The update addresses 114 security vulnerabilities—making it a high-priority patch for system safety. It also fixes an issue that left Neural Processing Units (NPUs) active during idle, yielding measurable battery life gains on modern laptops.

Usability and Sharing

File Explorer now shows a "Recommended" homepage for frequently used or recent downloads (requires a Microsoft account). QR code sharing was expanded beyond Wi‑Fi to include website links, cloud files, and Mobile Hotspot connections. Dark Mode consistency and small Start menu improvements (account management, drag-and-drop to the taskbar) round out the user-facing changes.

Critical Issues Identified

Azure Virtual Desktop Authentication Failure

Several users report AVD connections failing with authentication error 0x8008005 after installing KB5074109. This blocks remote desktop workflows and is considered the most severe problem. The only confirmed workaround so far is uninstalling the update.

Gaming Performance Drops (NVIDIA)

Numerous reports indicate gaming frame rates falling—roughly a 20 FPS loss in some cases—on systems with NVIDIA GPUs after the update. If you prioritize gaming performance, this is a compelling reason to postpone installation.

Other Reported Bugs

There are additional reports of Windows failing to format USB flash drives to FAT32. While less widespread, this can disrupt simple tasks like preparing installation media or portable drives.

Should You Install KB5074109?

For general home users focused on security, installing KB5074109 is recommended because it patches 114 vulnerabilities and improves battery life on NPU devices. Professionals who depend on Azure Virtual Desktop, remote desktop access, or uncompromised gaming performance should delay applying this update until Microsoft issues fixes.

Workarounds and Rollback

If you experience problems, uninstall KB5074109 via Settings > Windows Update > Update history > Uninstall updates. Monitor Windows Update announcements and Microsoft Support for a follow-up patch addressing AVD and gaming issues.

Build Number Changes

After installation the OS build numbers will change to:

  • Version 24H2: build 26100.7623
  • Version 25H2: build 26200.7623

Keep backups and test updates on nonproduction machines when possible, especially if you depend on AVD or high-performance gaming hardware.

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