Microsoft's optional update for Windows 11, KB5120998, is causing issues with mouse cursor settings, reverting them to default configurations after installation. Users are experiencing frustrations as personalized cursors are replaced by an oversized default version, and adjustments to color and size often do not persist. This problem appears to be linked to specific hardware configurations or display scaling setups. Microsoft is investigating the issue, and users can uninstall the update to resolve the problem without affecting access to essential security patches.