Microsoft has fixed a known issue that wiped mouse settings on some Windows 11 systems after installing the KB5120998 August 2026 preview update.
According to user reports, mouse cursor personalization settings automatically changed or reset after installing this buggy update, and users couldn’t restore them even after uninstalling KB5120998 from affected devices.
Microsoft confirmed the issues on Friday, one day after releasing KB5120998, which brought Start menu, taskbar, and Windows search improvements to devices running Windows 11 versions 24H2 and 25H2.
As the company later explained, the issues stem from “code components” in non-English Windows installations, which cause settings load failures and result in a default being used instead.
“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,” Microsoft said.
“In impacted locales, these settings will fail to load, causing a default to be used instead. Attempting to manually restore the settings values is not successful, as the issue prevents loading these settings regardless of their value.”
On Tuesday evening, Microsoft said it had resolved the bug in the KB5124008 September 2026 cumulative update and advised users to update their devices.
“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 noted.
KB5120998 is an optional update that requires users to click the “Download and install” link, reducing the number of potentially affected Windows users. However, it will install automatically if the “Get the latest updates as soon as they’re available” option is toggled on.
In recent months, Microsoft has addressed several other issues causing mouse problems on Windows devices.
For instance, in October, it released emergency updates to fix a known issue that made the Windows Recovery Environment (WinRE) unusable by disabling USB mice and keyboards, and, more recently, it confirmed an ongoing investigation into a bug causing the mouse pointer to disappear for some classic Outlook users when moving it over the interface.
On Tuesday, Microsoft also resolved a known issue that wiped custom desktop settings on some Windows devices after installing the KB5120998 preview update.
Overall prevention scores can hide what happens after initial access. Once attackers are using valid credentials, prevention drops sharply.
The Blue Report 2026 measures defenses technique by technique across 338 million simulations run in customer production environments.
