Microsoft has addressed a significant issue that emerged following the installation of the KB5120998 August 2026 preview update on certain Windows 11 systems. Users reported that their mouse settings, particularly those related to cursor personalization, were unexpectedly altered or reset after applying this update. Even attempts to revert these changes by uninstalling the update proved futile for many, as the settings remained elusive.
Clarification from Microsoft
In a statement released on Friday, just a day after the rollout of KB5120998, Microsoft acknowledged the problem. This update was intended to enhance the Start menu, taskbar, and Windows search functionalities for devices operating on Windows 11 versions 24H2 and 25H2. However, the company identified that the root cause of the issue lay within “code components” specific to non-English Windows installations. This flaw led to failures in loading personalized settings, defaulting instead to standard configurations.
Microsoft elaborated, stating, “Following installation of Windows updates released August 27, 2026 (KB5120998), mouse personalization settings are being reverted to certain standard settings. This includes cursor and cursor animations that are selected in the Mouse Properties options under Windows.” The company further explained that in affected locales, the settings would fail to load, rendering manual restoration attempts ineffective.
Resolution and Recommendations
On Tuesday evening, Microsoft announced that the bug had been resolved in the subsequent KB5124008 September 2026 cumulative update. Users were encouraged to update their devices to benefit from this fix. The company noted, “This issue was resolved by Windows updates released September 8, 2026 (KB5124008), and later. We recommend you install the latest security update for your device as it contains important improvements and issue resolutions, including this one.”
It is worth mentioning that KB5120998 was an optional update, requiring users to actively select the “Download and install” link, which may have limited the number of affected users. However, for those who had enabled the “Get the latest updates as soon as they’re available” feature, the update would have installed automatically.
Broader Context of Mouse Issues
In recent months, Microsoft has been proactive in addressing various mouse-related issues impacting Windows devices. For example, in October, the company released emergency updates to rectify a problem that rendered the Windows Recovery Environment (WinRE) unusable by disabling USB mice and keyboards. Additionally, Microsoft is currently investigating another bug that causes the mouse pointer to disappear for some classic Outlook users when navigating the interface.
On the same day as the resolution for the mouse settings issue, Microsoft also announced the fix for a known problem that resulted in the loss of custom desktop settings on certain Windows devices after the installation of the KB5120998 preview update.
