Windows Powershell cannot be stopped from coming up again.

If Windows PowerShell keeps returning after reboot, the startup trigger is likely not the Task Manager entry alone. Check the other common startup locations and disable the item that launches powershell.exe.

1. In Task Manager (Ctrl + Shift + Esc), open the Startup apps tab and disable any entry related to Windows PowerShell.
2. Open Settings > Apps > Startup and turn off anything related to PowerShell or Terminal.
3. Check the Startup folder:
   • Press Win + R
   • Run shell:startup
   • Remove any shortcut that starts PowerShell or Windows Terminal.
4. Check Task Scheduler for a logon or startup task that runs PowerShell:
   • Open Task Scheduler
   • Review scheduled tasks and look for actions that start powershell.exe
   • Disable the matching task
5. If the popup still returns, disable scheduled startup items one at a time, restart, and test after each change to identify which task is causing it.

If the PowerShell window is being opened by an old script or scheduled task, Windows 11 uses Windows PowerShell 5.1 by default, and older startup items can continue to relaunch it until the startup entry or task is removed.

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