Microsoft’s latest optional Windows 11 update, KB5120998, is causing problems for some users, including changes to mouse cursor settings, disappearing wallpaper customizations and reports of blurry text. The update was released on August 27 for Windows 11 versions 24H2 and 25H2, but reports of unexpected behavior have emerged shortly after installation.
The update moves Windows 11 version 24H2 systems to build 26100.9278 and version 25H2 systems to build 26200.9278. Because it is an optional preview update, most users can choose whether to install it. However, those who have already installed it are reporting several personalization and display-related issues.
Mouse Cursor Settings Reset
One of the most noticeable problems linked to KB5120998 involves customized mouse pointers.
Some users have reported that their cursor suddenly becomes much smaller or larger than their preferred setting. Others say their customized cursor is replaced with the standard white Windows pointer after installing the update.
The problem can also affect settings changed through Windows accessibility and personalization options. Users may select a different cursor size, color or design, only to find that Windows later returns to the default configuration.
Microsoft has acknowledged reports involving cursor personalization settings being changed or reset following recent Windows updates. The company is currently investigating the issue.
For people who rely on larger or customized pointers for accessibility, the problem can be particularly frustrating because their preferred settings may disappear without warning.
Desktop Wallpapers Turn Black
Mouse settings are not the only personalization feature affected.
Some Windows 11 users say their desktop wallpaper is replaced by a completely black background after installing KB5120998. Manually selecting another wallpaper can restore the desktop temporarily, but some users report that the black background returns after signing out or restarting their computers.
Reports suggest that the issue does not affect every system. Some users have experienced both the cursor and wallpaper problems on the same computer, while others have encountered only one of the issues.
The exact cause remains unclear. Differences in hardware configurations, display scaling and personalization settings could potentially influence which systems experience the bugs.
Blurry and Pixelated Text
Another issue reported by a smaller group of users involves text rendering.
Affected users say text can appear blurry, pixelated or less sharp following installation of the update. Some have attempted to correct the problem using Windows’ ClearType text configuration, but that has not resolved the issue for everyone.
There are also reports of DISM error 0x800f0915 appearing during attempts to repair Windows. However, this particular error has been seen on previous Windows builds as well, so there is currently no clear evidence that it is directly caused by KB5120998.
These reports make it difficult to determine whether all of the problems share a single underlying cause.
The Update Is Optional
An important point for Windows 11 users is that KB5120998 is an optional preview update.
Unlike a regular security update that users may be expected to install promptly, optional preview updates are generally intended to allow users and organizations to test upcoming fixes and features before they are included in broader releases.
The update includes several Windows 11 improvements, such as additional taskbar customization options, a resizable Start menu and changes to Search.
Microsoft’s official support information has not listed these reported problems as formally recognized known issues for the update. Microsoft software engineer Jen Gentleman has also reminded users that the update is optional and encouraged people experiencing problems to submit detailed reports through Feedback Hub.
How to Remove KB5120998
Users who have installed KB5120998 and are experiencing these problems can consider uninstalling the update.
The process can be completed through Windows Settings:
Settings → Windows Update → Update History → Uninstall updates
Find KB5120998 in the list, select it and choose the option to uninstall. Windows may require a restart before the changes take effect.
Reports from some affected users indicate that removing the update restores their previous mouse cursor and wallpaper settings.
However, uninstalling the preview update also removes the new features and improvements it introduced. Those features should become available again when Microsoft incorporates them into a future Windows release.
Microsoft Investigating the Problems
The reported issues show why optional preview updates can sometimes be risky for users who depend on a stable Windows environment.
Although KB5120998 introduces several useful changes, problems involving personalization, wallpapers and text rendering can make the update inconvenient for affected computers.
Microsoft is investigating the cursor-related reports and is expected to address confirmed bugs through a future Windows update. At present, there is no announced date for a specific fix.
For users who have not yet installed the preview update, waiting for the next stable release may be the safer choice if their computer is used for important work.
Those already experiencing problems should monitor Microsoft’s support channels and Feedback Hub for further information. Until a permanent solution becomes available, uninstalling KB5120998 remains an option for users whose systems have been noticeably affected.
