Microsoft has officially acknowledged an issue affecting some Windows devices following the installation of the KB5120998 preview update released in August 2026. Users have reported that their desktop settings, including wallpaper and themes, have been reset or lost entirely, often reverting to a solid black background.
Details of the Issue
This known issue primarily impacts systems running Windows 11 versions 24H2 and 25H2. According to Microsoft, the problem arises after the installation of the updates released on August 27, 2026. The company noted, “Following installation of Windows updates released August 27 2026 (KB5120998) and later, some Windows Desktop settings fail to load, resulting in desktop backgrounds displaying as a solid black color.” In addition to wallpaper changes, users may also find their desktop themes and other settings affected.
Microsoft elaborated on the implications of this bug, stating, “On affected devices, attempting to manually restore customized settings does not work. This is because the issue prevents the correct loading of settings, regardless of their value. In this case, a default black background is used instead.” This means that users are unable to revert to their previous desktop configurations, leaving many frustrated.
Update Background
The KB5120998 update, launched with enhancements to the Start menu, taskbar, and Windows search for Windows 11 versions 25H2 and 24H2, was intended to improve user experience. However, it inadvertently introduced complications, including alterations to mouse settings, which also cannot be restored once changed.
As an optional, non-security update, KB5120998 requires users to actively select the “Download and install” option. However, for those who have enabled the “Get the latest updates as soon as they’re available” feature, the update installs automatically, potentially catching users off guard.
This is not the first time Microsoft has faced such a challenge. A similar bug emerged in February 2020 with the KB4539602 update, which disrupted desktop wallpaper functionality, causing Windows 7 wallpapers in ‘Stretch’ mode to display a blank black screen. Microsoft’s history with these types of issues underscores the complexities involved in maintaining a seamless user experience across its operating systems.
