Microsoft says a known issue that reverts mouse settings after installing the KB5120998 August 2026 preview update affects only non-English Windows 11 systems.
The bug was confirmed Friday, one day after the KB5120998 release, which includes Start menu, taskbar, and Windows search improvements for devices running Windows 11 versions 25H2 and 24H2.
According to user reports, mouse cursor personalization settings are changing or resetting automatically after installing the KB5120998 update, and affected Windows 11 users cannot restore their previous mouse settings after they are reverted.
“Following installation of Windows updates released August 27 2026 (KB5120998) and later, mouse personalization settings are being reverted to certain standard settings,” Microsoft explained at the time.
“This includes cursor and cursor animations that are selected in the Mouse Properties options under Windows.”
Only non-English Windows devices affected
In a Tuesday update to the Windows release health dashboard, the company noted that a follow-up investigation revealed the issue affects only non-English devices.
“Our investigation indicates that this issue is caused by code components used in non-English Windows installations. In impacted locales, these settings will fail to load, causing a default to be used instead,” Microsoft said.
Since KB5120998 is an optional, non-security update, users must click the “Download and install” link. However, if the “Get the latest updates as soon as they’re they’re available” option is enabled, the preview update will install automatically.
Microsoft has addressed several other issues causing mouse issues on Windows devices in recent months.
For instance, it released emergency updates in October to fix a known issue that made the Windows Recovery Environment (WinRE) unusable by disabling USB mice and keyboards.
More recently, Microsoft confirmed that it’s investigating a bug causing the mouse pointer to disappear for some classic Outlook users when moving it over the interface.
On Wednesday, it also acknowledged that Windows desktop settings will be lost or reset on some devices after installing the KB5120998 preview update.
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