On January 30, 2026, Microsoft released KB5074105, the latest non-security update for Windows 11 versions 25H2 and 24H2. Like it usually goes with the so-called C-updates, KB5074105 is a completely optional update, which means you can skip it if you do not want to install another patch. However, Microsoft has a few very valid reasons for you to actually get it right now.
Non-security updates for Windows 11 usually bring quite a lot of notable changes, new features, and improvements (all but security updates, hence the name). One of those improvements in KB5074105 is a fix for File Explorer and the shell breaking in specific scenarios. Release notes for the January 2026 non-security update confirm that certain users may have explorer.exe hanging on launch. Instead of getting you to the desktop as usual, you would get a system without the taskbar and a non-responsive shell.
KB5074105 fixes that bug. Here is what Microsoft says in the release notes:
[Logging into your PC] Fixed: This update addresses an issue where Explorer.exe might stop responding (hang) the first time you sign in to your PC, if certain apps were configured as startup apps. This could make the taskbar not appear.
A fix for the non-working tab is not the only important change in KB5074105. One security feature no longer requires a clean Windows installation in certain cases, plus the operating system now has an extra protection layer for its system files by forcing a UAC prompt when accessing storage settings.
Additionally, Microsoft fixed activation issues when upgrading Windows and system hanging when launching Windows Terminal as Administrator. And if your system suffers from desktop icons randomly rearranging themselves, KB5074105 will fix that for you as well. You can check out the complete changelog for the update here.