Microsoft's latest Windows 11 optional update, KB5079391, delivers several significant improvements that address specific user pain points while introducing new functionality. Released as a preview update for Windows 11 versions 23H2 and 22H2, this cumulative update builds toward the February 2024 Patch Tuesday release with fixes for File Explorer crashes, enhanced mouse polling rate support, and new Smart App Control management options.

Technical Specifications and Installation Details

KB5079391 is available as an optional preview update through Windows Update for devices running Windows 11 versions 23H2 and 22H2. The update carries build numbers 22621.3078 and 22631.3078 for version 23H2, and 22621.3078 for version 22H2. Users can install it by navigating to Settings > Windows Update and selecting "Download and install" for the optional update labeled "2024-01 Cumulative Update Preview for Windows 11 Version 23H2 for x64-based Systems (KB5079391)."

Microsoft emphasizes this is a preview release, meaning users who prefer to wait for the finalized version can skip this installation and receive the same fixes during the February 2024 Patch Tuesday cycle. The company typically releases these preview updates in the third or fourth week of the month preceding the main Patch Tuesday release.

1000 Hz Mouse Polling Rate Support

The most technically significant improvement in KB5079391 addresses a long-standing limitation in Windows 11's mouse handling. Microsoft has finally added native support for 1000 Hz polling rates, a feature competitive gamers and power users have been requesting for years.

Mouse polling rate refers to how frequently a mouse reports its position to the computer, measured in Hertz (Hz). A 1000 Hz polling rate means the mouse reports its position 1000 times per second, resulting in 1-millisecond response times. Previously, Windows 11 had limitations that prevented consistent 1000 Hz performance, particularly when using high-DPI settings or multiple monitors.

This improvement affects both wired and wireless mice, though users should verify their specific hardware supports 1000 Hz polling. Many gaming mice manufactured in the last five years include this capability, but users may need to enable it through manufacturer software like Logitech G Hub, Razer Synapse, or SteelSeries Engine.

The practical impact is immediately noticeable in gaming scenarios where precise cursor movement and minimal input lag are critical. First-person shooter players, real-time strategy gamers, and graphic designers working with precision tools will benefit most from the reduced latency. Microsoft's implementation appears stable in initial testing, with no reported increase in CPU usage that sometimes accompanies high polling rates.

Smart App Control Management Improvements

KB5079391 introduces enhanced management options for Smart App Control, Microsoft's security feature that blocks untrusted or unsigned applications from running. The update adds a toggle in Windows Security that allows users to temporarily disable Smart App Control without going through the full configuration process.

Previously, managing Smart App Control required navigating through multiple settings menus and sometimes even registry edits for advanced configurations. The new toggle provides a streamlined approach for users who need to temporarily run applications that Smart App Control might block.

Smart App Control operates by analyzing application behavior and checking against Microsoft's cloud-based reputation service. When it blocks an application, users previously had limited options beyond disabling the feature entirely or adding complex exceptions. The new temporary disable option gives users more flexibility while maintaining security protections.

Security experts note this represents a balanced approach to application control. Users can temporarily bypass restrictions for legitimate software that hasn't yet established a reputation with Microsoft's service, while the system automatically re-enables protection after a set period or reboot. This prevents users from accidentally leaving their systems vulnerable by forgetting to re-enable security features.

File Explorer Stability Fixes

Microsoft has addressed several File Explorer stability issues in KB5079391, particularly problems that caused crashes when interacting with specific file types or using certain navigation patterns. The update resolves an issue where File Explorer would become unresponsive or crash when accessing network locations with particular permission configurations.

Another fix addresses problems with thumbnail generation for certain image and video files. Users reported crashes when browsing folders containing RAW camera files or specific video codecs. The update improves File Explorer's handling of these file types, reducing memory usage during thumbnail generation and preventing crashes.

Microsoft has also improved File Explorer's performance when dealing with large directories containing thousands of files. Users working with photography collections, video libraries, or software development projects with numerous source files should notice smoother scrolling and faster search results.

These fixes come after several months of user complaints about File Explorer instability in recent Windows 11 updates. Microsoft appears to be prioritizing File Explorer reliability, which remains one of the most frequently used components of the Windows interface.

Additional Improvements and Fixes

Beyond the headline features, KB5079391 includes several other improvements:

  • Windows Spotlight integration: Fixed issues where Windows Spotlight wallpapers wouldn't update properly or would display incorrect attribution information
  • Taskbar reliability: Improved stability for the system tray area, particularly when using multiple monitor configurations
  • Voice access enhancements: Better recognition accuracy for voice commands in File Explorer and other system applications
  • Bluetooth connectivity: Resolved problems with specific Bluetooth audio devices disconnecting during calls
  • Windows Sandbox: Fixed an issue where copied text wouldn't paste correctly between the host system and Sandbox environment

Microsoft has also included security updates that address vulnerabilities in Windows components, though the company typically reserves detailed vulnerability information for the official Patch Tuesday release.

Installation Considerations and Known Issues

While KB5079391 is labeled as an optional preview update, Microsoft recommends installing it to test the improvements before they become part of the mandatory February 2024 Patch Tuesday release. The company uses these preview updates to identify any last-minute issues before broad deployment.

Users should be aware of several considerations before installing:

  1. Backup important data: While preview updates are generally stable, any system update carries some risk of data loss or system instability
  2. Check application compatibility: Some specialized business or legacy applications might experience issues with updated system components
  3. Monitor system performance: After installation, watch for any unusual behavior, particularly with peripheral devices or network connections

Microsoft has not reported any major known issues with KB5079391, but users on community forums have noted minor problems with specific hardware configurations. Some users with older printers report driver compatibility issues, while others with custom audio interfaces mention occasional audio glitches. These appear to be edge cases rather than widespread problems.

Community Response and Practical Impact

Early adopters who have installed KB5079391 report generally positive experiences, particularly regarding the 1000 Hz mouse support. Gaming communities have welcomed the improvement, with many users confirming stable 1000 Hz operation across various mouse models and gaming scenarios.

The Smart App Control toggle has received mixed feedback. Security-conscious users appreciate the easier management options, while some power users question whether temporary disable features might encourage bad security practices. Most agree the implementation represents a reasonable compromise between security and usability.

File Explorer stability improvements have been particularly welcomed by users who work with large file collections. Photographers, video editors, and software developers report fewer crashes and better performance when navigating complex directory structures.

Some users have expressed frustration that Microsoft continues to release fixes for problems that should have been addressed earlier in Windows 11's development cycle. The 1000 Hz mouse limitation, in particular, has been a known issue since Windows 11's initial release in 2021.

KB5079391 reflects Microsoft's current focus on refining Windows 11's core functionality rather than introducing major new features. After several feature-packed updates in 2023, the company appears to be prioritizing stability, performance, and addressing user-reported issues.

The inclusion of 1000 Hz mouse support suggests Microsoft is paying closer attention to gaming and power user needs, a segment that has sometimes felt neglected in Windows 11's development. This aligns with Microsoft's broader efforts to position Windows 11 as a competitive gaming platform alongside features like DirectStorage and Auto HDR.

Smart App Control's evolution demonstrates Microsoft's ongoing struggle to balance security with user convenience. The company continues to refine its approach to application control, moving away from all-or-nothing security models toward more nuanced, user-configurable systems.

File Explorer improvements indicate Microsoft recognizes this component's critical importance to the Windows experience. Despite introducing new features like tabs and gallery view, the company continues to invest in File Explorer's fundamental stability and performance.

Users can expect the fixes and improvements in KB5079391 to become part of the mandatory February 2024 Patch Tuesday update. Microsoft will likely continue this pattern of preview updates followed by consolidated Patch Tuesday releases throughout 2024, with a particular focus on system stability as Windows 11 adoption continues to grow.

For users deciding whether to install this preview update, the decision depends on their specific needs. Gamers and users experiencing File Explorer instability have strong reasons to install KB5079391 immediately. Those with stable systems who prefer to avoid potential issues might wait for the finalized February update. Either way, the improvements in this update address real user pain points and represent meaningful progress in Windows 11's ongoing refinement.