Windows 11 KB5067036 Bug Causes Task Manager Instances to Duplicate on Close
Windows 11 update KB5067036 has been reported to cause a strange bug where the Task Manager duplicates its instances every time it is closed. Although Microsoft hasn’t officially acknowledged these reports yet, about 30% of the 100 virtual machines tested by our team encountered this unusual issue.
If you frequently open Task Manager multiple times a day, be cautious—as this bug could negatively impact your PC’s performance.
About KB5067036
KB5067036 (Build 26200.7019 or 26100.7019) was released as an optional update on October 28. This update introduces a new Start menu that is rolling out gradually, along with several other enhancements:
- New, colorful battery icons in the taskbar
- A Recommended feed in File Explorer
- Improved shutdown behavior when using Update & Shut Down from the Start menu’s power options
Additionally, the update addresses a Task Manager issue where apps and their processes were not grouped correctly, causing confusing performance reports.
Task Manager Bug Details
While the update appears promising on paper, some users have encountered a critical bug related to Task Manager. According to our tests and observations at Windows Latest, Build 26200.7019 or 26100.7019 breaks the functionality of the Task Manager’s close ( ‘X’ ) button on certain PCs.
When affected users try to close Task Manager using the close button, the app does not quit as expected. Instead, it continues running in the background. Each time Task Manager is opened and closed again, an additional process remains active. In one extreme test, opening and closing Task Manager about 100 times resulted in 100 running instances, each consuming roughly 20-25 MB of RAM—totaling around 2 GB of memory usage. This situation could cause significant performance issues, especially on low-end hardware.
How to Fix or Work Around the Issue
The Task Manager “ghost instances” bug is not widespread but can affect some users after installing KB5067036. If you encounter this issue, avoid closing Task Manager using the ‘X’ button. Instead, use these alternatives to properly close Task Manager:
- Use the End task option within Task Manager to close it safely.
- Run the following command in Command Prompt to terminate all Task Manager instances at once:
taskkill /im taskmgr.exe /f
These methods help you prevent excessive background Task Manager processes from accumulating.
Conclusion
While Windows 11 KB5067036 offers useful new features and improvements, this unexpected Task Manager bug can seriously affect system performance for some users. Hopefully, Microsoft will address this issue in an upcoming patch. In the meantime, use the recommended workarounds to keep your PC running smoothly.
https://www.windowslatest.com/2025/10/30/windows-11-kb5067036-issue-task-manager-wont-close-and-duplicates-may-hurt-performance/