Microsoft’s August optional update for Windows 11 is meant to be one of the more welcome releases in months, delivering the movable taskbar, a resizable Start menu, and a decluttered Search box. But a fast-growing pile of user reports says the same patch is also breaking cursor customization and resetting desktop wallpapers for a large number of people. Based on what we’re seeing across Feedback Hub and community forums, we recommend holding off on installing Windows 11 KB5120998 until Microsoft ships a fix.
- Status: Confirmed and under investigation. Microsoft has acknowledged the cursor complaint in Feedback Hub but has not yet published a formal known-issue notice for the cursor or wallpaper problems.
- Affected build: Windows 11 Build 26200.9278, shipped as the August optional update KB5120998.
- Symptoms: Custom cursors revert to a large, white, default pointer; desktop backgrounds reset to solid black; and some users hit a DISM error 0x800f0915 when repairing the system image.
- Workaround: Uninstalling KB5120998 through Windows Update history resolves both the cursor and wallpaper issues for those who tried it.
The features you’d get if you install it
Before weighing the risks, it helps to know what this optional update actually offers. According to the update’s own changelog, Windows 11 KB5120998 (Build 26200.9278) adds the long-requested movable taskbar, a resizable Start menu, and a cleaned-up Search box. These are the headline features Windows 11 users have been asking for, and they arrived as part of this optional release rather than a full feature drop.
Microsoft also provided direct download links for an offline installer (MSU) so users who prefer to stage updates manually can grab the package directly. In short, the update is feature-forward, which is exactly why the accompanying bugs are frustrating: people installed it expecting gains, not regressions.
#1 Custom cursors revert to a big white pointer
The most common complaint is that the mouse pointer resets to a larger, white, Windows 98-style cursor that refuses to change back. As one user described it, after installing Build 26200.9278 (KB5120998) their custom HiDPI cursor was gone and replaced by a big white one. Rolling back to the previous build fixed it for them.
Others reported the same wall. One person said it became impossible to change the pointer to anything other than the default, while another said the cursor “is always white and enlarged” and that the accessibility selectors meant to change it had no effect. A few users also noted the cursor’s tail looks noticeably longer, which looks like a mix-up between the older Aero pointer and whatever new theming logic the update introduced.
One Feedback Hub user put it plainly: after installing the update, the pointer fell back to the default (none) mode and would not respond to their custom cursors or system themes like Windows Black. They also flagged that their wallpaper had flipped to a solid color, though they could change it back afterward. Microsoft has since responded to that post, confirming it received the complaints and is looking into the matter.
#2 Desktop wallpaper resets to solid black
The second major complaint is a desktop background wiped out and replaced with a flat black color. One user wrote that on both their desktop and laptop they got a black wallpaper after installing this update and had to reset it themselves, with several replies echoing “Same.”
Several people hit both bugs at once. One user said the update set their wallpaper to a single black color and likely made their normal cursor slightly larger. Another added that the wallpaper kept reverting to black after logout or restart, even after manually setting it back, until the update was removed.
Not everyone is affected. Several commenters, including a thread moderator, reported zero issues across multiple machines, and I personally saw neither problem after installing the update. That variability is a good example of why Microsoft rolls updates gradually: these cursor and wallpaper issues may tie to specific hardware, display scaling, or theme configurations rather than hitting every PC that installs Windows 11 KB5120998. That said, the volume here is higher than the usual minor bug reports.
#3 A DISM repair error shows up
A handful of users also mentioned a DISM error, 0x800f0915, when trying to repair their system image after installing the update. This error has circulated for months across several previous Windows 11 builds and is generally caused by DISM being unable to reach a valid repair source, rather than something KB5120998 introduced. It should be treated as a separate, ongoing issue rather than a direct result of this patch.
What Microsoft has said so far
Jen Gentleman, a Microsoft software engineer, responded in the Reddit thread, reminding people that Windows 11 KB5120998 is optional and that skipping it means the same changes arrive in the next mandatory update anyway. She asked affected users to file reports through Feedback Hub with as much detail as possible.
No mention was made of the cursor or wallpaper bugs specifically, and Microsoft has not published anything acknowledging either issue as a known problem yet, beyond a “we’ve got it” alert inside Feedback Hub. We expect a formal known-issue notice at some point, and Microsoft is no stranger to Known Issue Rollback (KIR), the process it uses to pull back a problematic update fleet-wide. There is no timeline for that yet.
What this means for you
For most everyday users, the message is simple: wait. Both bugs are easy to trigger, both are widely reported, and the only confirmed fix right now is uninstalling the update completely, which also strips out the taskbar, Start menu, and Search improvements everyone was waiting for. That is a poor trade-off.
If you are an IT admin managing a fleet, this is a clear case to pause deployment of the optional update via Windows Update for Business or Intune until Microsoft acknowledges and resolves the issues. The DISM error 0x800f0915 is unrelated, so do not let it muddy your decision about the cursor and wallpaper regressions.
How to get it (or what to do if you already installed it)
If you want to skip the update entirely, simply decline the optional Windows 11 KB5120998 offer in Windows Update and keep your current build. If you already installed it and everything looks fine, but the three headline features have not shown up yet, you can force them on manually instead of waiting for the gradual rollout to reach you.
If the cursor or wallpaper bugs have already hit you, the reliable fix today is to uninstall KB5120998 through Windows Update history. Once Microsoft publishes a fix or runs a Known Issue Rollback (KIR), reinstalling will be the clean path forward. Until then, sitting this one out is the safest move.
Source: Windows Latest
Build details:
- kb5120998
Over to you: Have you installed Windows 11 KB5120998 yet, and did you run into the cursor or wallpaper issues, or are you waiting it out?
