Imagine your computer's Task Manager, the go-to tool for troubleshooting and managing system performance, turning into a resource-hungry zombie lurking in the background. That's exactly what's happening for some Windows 11 users after a recent update. A newly discovered bug is causing Task Manager to remain active even after you think you've closed it, potentially slowing down your system and causing instability. But here's where it gets controversial: this issue emerged after Microsoft's cumulative update KB5067036, released on October 28, 2025, which many users received automatically, seemingly without clear warning that it might be unstable.
According to Microsoft's official statement (https://learn.microsoft.com/en-us/windows/release-health/status-windows-11-25h2#3707msgdesc), simply clicking the [X] button to close Task Manager doesn't fully shut it down. Instead, the taskmgr.exe process continues running invisibly in the background. Each time you reopen and close Task Manager, another instance is created, quietly consuming your system's resources. While Microsoft has marked the issue as “mitigated” in build 26100.7019, a permanent fix is still in the works.
Windows Task Manager is a cornerstone utility for both everyday users and IT professionals, offering insights into CPU/GPU usage, memory consumption, and overall system performance. It's the go-to tool for diagnosing problems and shutting down unresponsive applications. So, when it malfunctions, it's more than just an inconvenience—it's a potential system-wide headache.
The problem first gained widespread attention on Reddit (https://www.reddit.com/r/Windows11/comments/1oj7vd1/psawindows1125h2262007019taskbarmanager/), where users reported noticeable performance drops, increased application stuttering, and even system instability. Some tech-savvy users running CPU benchmark tools like CPU-Z confirmed that the performance degradation worsened with each additional background instance of Task Manager. And this is the part most people miss: both Windows 11 versions 25H2 and 24H2, across builds 26100.7015 and 26200.7015, are affected by this issue.
Microsoft has labeled KB5067036 as a “preview” update, but many users enabled the option to “get the latest fixes and performance improvements” without realizing they might be opting into potentially untested software. This has sparked criticism over Microsoft's update testing procedures, with some Reddit users feeling they were unknowingly enrolled in a beta testing program. One user even reported that 30% of systems in their virtualized test environment exhibited the bug after applying the update.
Is Microsoft moving too fast with updates at the expense of stability? Let us know your thoughts in the comments.
Until a full fix is released, Microsoft has provided temporary workarounds:
- Manual Process Termination: Open Task Manager, right-click on the Task Manager process in the Processes tab, and select “End Task.”
- Command Line Method: Open an elevated Command Prompt and run
taskkill /im taskmgr.exe /fto forcefully terminate all active Task Manager instances. - Registry Tweaks: Advanced users can explore registry-level fixes (https://www.elevenforum.com/t/resolve-task-manager-process-might-continue-to-run-in-background-after-app-is-closed.41605/) that re-enable specific feature flags affecting Task Manager's behavior. However, this method requires administrative privileges and careful editing.
To avoid the issue altogether, users are advised to refrain from using the [X] button to close Task Manager and instead terminate it manually or via command-line tools. Those concerned about system stability may also consider rolling back the KB5067036 update or disabling the “get the latest updates” setting in Windows Update to avoid preview releases.
Microsoft has yet to provide a timeline for the fix but has confirmed ongoing investigations. Given Task Manager's critical role, a resolution is expected soon, likely in an upcoming cumulative or out-of-band update. In the meantime, stay tuned for updates by following us on X/Twitter (https://twitter.com/CyberInsidercom) and LinkedIn (https://www.linkedin.com/company/cyberinsider/) for more exclusive tech insights.
