Microsoft has confirmed that the KB5120998 August 2026 non-security preview update is reverting mouse settings on Windows 11 systems.
According to user reports, mouse cursor personalization settings are either being changed or reset automatically after installing the KB5120998 update.
More importantly, affected Windows 11 users will not be able to restore the previous mouse settings after they are reverted.
"Microsoft has received reports indicating that mouse cursor personalization settings are being changed or reverted to certain standard settings. This occurs following installation of Windows updates released August 27 2026 (KB5120998) and later," Microsoft explained.
"The issue is described as resulting in appearance regressions and intermittent animation changes. Some reports mention that high-DPI mouse cursors are replaced with larger, white cursors, and custom cursor animations reverting to standard settings. Attempts to restore the previous cursor customization are reported to be unsuccessful."
Microsoft said that it's still investigating the root cause and asked affected customers to file a report via the Feedback Hub if they're experiencing this issue.