Windows 11 updates are supposed to make a computer more reliable, not leave basic system tools running after they are closed. The KB5067036 Task Manager bug became a sharp reminder of that problem. This optional preview update brought useful fixes, but it also created a strange background process issue that could waste resources, muddy troubleshooting, and make normal PC maintenance feel harder than it should.
KB5067036 And The Task Manager Bug
KB5067036 was released on October 28, 2025, as an optional preview update for Windows 11 version 24H2 and 25H2. It was not a required security update. It was a non-security preview release, which means it gave users and IT teams early access to fixes and improvements before some of those changes moved into a later cumulative update.
The problem was tied to Task Manager. After installing the update, closing Task Manager with the X button did not always fully end the process. The window disappeared, but taskmgr.exe could stay active in the background. Microsoft later documented the issue in the official KB5067036 release notes, noting that multiple lingering Task Manager instances could consume system resources and affect performance.
That is not a small detail. Task Manager is the tool people open when Windows feels slow, an app freezes, a startup item looks suspicious, or CPU and memory usage need to be checked. When the troubleshooting tool itself starts behaving strangely, it creates confusion fast.
For one open-and-close cycle, the impact may be minor. The larger problem comes from repetition. A user opens Task Manager, closes it, opens it again later, then closes it again. If each closed instance remains in the background, the process list can become cluttered with duplicate taskmgr.exe entries. That wastes resources and makes a PC look messier than it really is.
This was not malware. It was not user error. It was a documented Windows update bug that made a trusted diagnostic utility act like a stuck background process.
Optional Updates Are Not Urgent Fixes
The KB5067036 issue also exposed a common misunderstanding about Windows updates. Not every update deserves the same urgency. Security updates protect against vulnerabilities and should be treated seriously. Optional preview updates are different. They often contain quality fixes, feature changes, interface adjustments, and early improvements that are still moving through Microsoft’s broader release cycle.
Microsoft explains that optional non-security preview releases are usually released during the fourth week of the month and are separate from the regular monthly security update release. The Windows update release cycle makes this distinction important because preview updates can help test upcoming changes, but they are not mandatory patches for most home users or small business PCs.
That does not make optional updates bad. Some solve real problems. Some include useful improvements that users want early. KB5067036, for example, included a long-awaited fix for an issue where “Update and shut down” could restart a Windows 11 device instead of shutting it down. That was a good fix. The problem is that the same update also introduced the Task Manager bug.
That is the tradeoff with preview updates. They can solve one annoying issue while creating another. For a test machine, that risk may be acceptable. For a daily work PC, school laptop, gaming system, or business computer, stability usually matters more than early access.
A better update approach is simple:
- Install monthly security updates on a normal schedule.
- Delay optional preview updates unless they fix a specific problem.
- Read known issues before installing preview updates.
- Wait a few days to see whether major bugs are reported.
- Restart the PC after larger updates instead of leaving Windows half-refreshed.
The goal is not to avoid updates. The goal is to stop treating every optional update like an emergency.
Task Manager Is A Core Windows Tool
Task Manager is one of the most familiar Windows tools because it gives a quick view of what the system is doing. It shows running apps, background processes, CPU usage, memory usage, disk activity, network activity, startup apps, and service behavior. It is not flashy, but it matters.
When a program freezes, Task Manager is usually the first place people go. When a fan starts spinning hard, Task Manager helps show whether CPU usage is high. When a computer slows down after startup, Task Manager can reveal which apps are loading in the background. That is why a Task Manager bug feels different from a random app bug. It affects the tool used to understand other problems.
With the KB5067036 issue, the visible Task Manager window could disappear while the process stayed active. Microsoft’s Windows 11 resolved issue page described the result as multiple lingering taskmgr.exe instances that could consume resources and potentially degrade device performance.
That kind of behavior causes several practical problems. A laptop may lose battery faster than expected. A desktop may feel slightly heavier during multitasking. A gamer or creator may see less available memory. An IT technician may waste time sorting through duplicate entries while trying to diagnose something else.
It can also look suspicious. Most users are trained to worry when an app stays open after it is closed. In this case, the lingering process was tied to a Microsoft-confirmed bug, not an infection. Still, the behavior looked wrong because it was wrong.
Task Manager should open, show what is running, help end stuck apps, and close cleanly. Anything else makes troubleshooting harder than it needs to be.
How To Check For Stuck Task Manager
The easiest sign of the bug is Task Manager appearing in the process list after the app has been closed. If Task Manager is not visibly open but taskmgr.exe still appears, the process may be lingering in the background.
A simple Command Prompt check can confirm it. Open Command Prompt and run this command:
tasklist | findstr /i taskmgr
Microsoft’s tasklist command documentation explains that the command displays active processes on the local computer. In this case, it helps confirm whether taskmgr.exe is still running after the Task Manager window has been closed.
If no Task Manager window is open and the command still returns taskmgr.exe, the system may have one or more stuck Task Manager processes. That does not automatically mean the computer is infected or broken. In the context of KB5067036, it means Windows may be holding onto Task Manager after it should have closed.
The same check can also be done inside Task Manager itself. Open Task Manager, go to the Processes tab, and look for Task Manager entries. If more than one appears after repeated open-and-close cycles, the bug may be showing up.
This is the part that frustrated users. A tool that normally helps reveal system clutter was creating clutter of its own. Strange. Also very avoidable with a little update caution.
How To Close The Extra Processes
For users affected by the bug, Microsoft listed two practical workarounds while the issue existed. The first was to avoid closing Task Manager with the X button and instead end the Task Manager process from inside Task Manager. The second was to use Command Prompt to close multiple instances at once.
The most common command was:
taskkill /IM taskmgr.exe /F
Microsoft’s taskkill command documentation explains that the command can end tasks by image name or process ID. In this case, /IM taskmgr.exe targets Task Manager by image name, and /F forces termination.
That command should be used carefully, but it is straightforward. It closes all matching Task Manager processes. After running it, Task Manager should disappear from the active process list unless it is opened again.
The graphical method is easier for many users. Open Task Manager, select the Task Manager process, and choose End task. That closes the process without typing a command. If several duplicate instances exist, each one may need to be ended.
These steps are workarounds, not a proper fix. A normal Windows utility should not require manual cleanup after every use. The real fix came through later Windows updates, which is why systems that still show similar behavior should be brought current and restarted.
Removing A Bad Windows Update
When an optional update causes performance problems, uninstalling it can be reasonable. That does not mean every update should be removed at the first sign of inconvenience. It means a preview update that creates a visible problem may not be worth keeping, especially when it is not a required security patch.
Microsoft’s support page on how to uninstall a Windows update explains the standard process. On Windows 11, the usual route is Settings, Windows Update, Update history, then Uninstall updates. From there, the affected update can be selected if Windows allows it to be removed.
For KB5067036, that meant looking for the preview update in the installed update list and uninstalling it when necessary. A restart should follow. Restarting matters because it clears active processes, reloads Windows components, and gives the system a clean chance to behave normally again.
There is one important limitation. Some updates cannot be removed. KB5067036 also included a servicing stack update component, KB5067035. Servicing stack updates affect the part of Windows that installs updates, and they are treated differently from ordinary cumulative updates. In practical terms, not every component tied to a Windows update can be rolled back through the normal uninstall menu.
For most users, the cleanest path is still the Settings app. Command-line removal should be left for advanced troubleshooting or professional support. A mistyped package command can create more trouble than it solves.
The Fix Arrived Later
The Task Manager bug was real, but it was not permanent. Microsoft later marked the issue as resolved for affected Windows 11 versions, including version 25H2. The company’s Windows 11 resolved issue page listed the Task Manager background process issue and described workarounds for closing lingering instances while the problem existed.
That changes how the issue should be understood today. It is not a reason to avoid every Windows update. It is a reason to understand update timing. A resolved bug can still teach an important maintenance lesson.
The pattern is familiar. A preview update ships with useful changes. A strange bug appears. Microsoft documents the issue. Workarounds circulate. A later update resolves it. The system eventually stabilizes, but early installers deal with the mess first.
For home users, that can mean wasted time and frustration. For small businesses, it can mean lost productivity. A few computers behaving strangely after an optional update may not sound serious until those computers are used for billing, scheduling, customer service, design work, school assignments, or remote work.
The better lesson is practical. Security updates are important. Preview updates deserve patience. Waiting a short time before installing an optional release can prevent a lot of unnecessary troubleshooting.
Better Windows Update Decisions
Good Windows maintenance is not about refusing updates. It is about separating urgent protection from optional change. That difference matters more as Windows continues adding AI features, interface changes, background services, and deeper cloud-connected behavior.
Security updates should remain a priority because they patch vulnerabilities and reduce exposure to real threats. Optional preview updates should be handled more cautiously. They may include valuable fixes, but they can also introduce unexpected problems before the wider release cycle catches them.
Microsoft’s Windows Update FAQ explains that users can view update history and remove some installed updates when necessary. That is useful, but it should not become the main maintenance strategy. Prevention is easier than rollback.
A cleaner update routine looks like this:
- Check whether an update is security, cumulative, preview, or optional.
- Read known issues before installing a preview update.
- Delay optional updates on important work machines.
- Restart after major updates and check system behavior afterward.
- Keep backups current before larger Windows changes.
- Avoid installing preview updates just because they appear at the top of Windows Update.
This approach keeps Windows current without turning every PC into a test machine. It also helps reduce the stress that comes from strange post-update behavior.
The KB5067036 Task Manager bug was annoying because it involved a trusted utility. It was also useful as a warning. Optional does not mean harmful, but it also does not mean necessary.
How JENI® Supports PC Control
The KB5067036 bug is the kind of Windows problem that makes a PC feel less predictable. A tool closes, but the process keeps running. An update promises improvement, but it creates another issue. Performance drops, and the cause is not obvious at first glance.
JENI® is built around a different idea. It is an on-demand maintenance tool for Windows and Mac users who want cleanup, repair, and optimization without adding another always-running background burden. It is designed to be opened when maintenance is needed and closed when the job is done.
For Windows users, JENI® supports practical maintenance tasks such as system file checks, update repair steps, DNS and network refreshes, cleanup routines, and performance-focused system care. Those tools matter when Windows updates leave behind clutter, stuck services, temporary files, or confusing behavior.
The value is control. No constant nagging. No ads. No subscription pressure. No hidden background drain pretending to be helpful.
A Task Manager bug may sound small, but it points to a larger frustration. Users want computers that behave clearly. Open a tool, use the tool, close the tool. Done. JENI® supports that kind of cleaner PC experience by keeping maintenance direct, visible, and practical.
FAQ
Is KB5067036 a security update?
No. KB5067036 was an optional non-security preview update for Windows 11 version 24H2 and 25H2. It was not required in the same way as a monthly security update.
Can the Task Manager bug harm a PC?
The bug was not known to physically damage a PC or destroy files. The main concern was unnecessary background resource use, duplicate Task Manager processes, and confusion during troubleshooting.
How can stuck Task Manager processes be closed?
They can be closed by selecting Task Manager inside Task Manager and choosing End task. They can also be closed with Command Prompt by running taskkill /IM taskmgr.exe /F.
Should optional Windows updates be skipped?
Optional Windows updates do not need to be skipped forever, but they should not be installed blindly. On important PCs, waiting a few days and checking known issues is usually the better move.
Did Microsoft fix the Task Manager bug?
Yes. Microsoft later listed the Task Manager background process issue as resolved for affected Windows 11 versions. Systems that still show similar behavior should install current Windows updates and restart.
Keep Windows Updates Under Control
The Windows 11 KB5067036 Task Manager bug was strange, frustrating, and memorable because it affected a tool people rely on when something else goes wrong. Task Manager is supposed to help explain system behavior. It should not become another background process problem.
The larger lesson is simple. Optional preview updates should be treated like early access, not automatic must-installs. Security updates deserve urgency. Preview updates deserve patience. That small difference can prevent wasted time, surprise slowdowns, and needless troubleshooting.
A clean, reliable PC comes from smart update choices, steady maintenance, and tools that respect system resources. JENI® helps support that goal by giving users practical maintenance options without turning into another invisible background burden.
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