Win 10 start unresponsive

Update 04 Jan 2018
Troubleshoot problems with the Start menu Win 10
Windows: The Start Menu in Windows 10 is useful, but it’s not perfect. Sometimes tiles go missing, or it won’t open at all when you click it or press the Windows key. Other times the tiles don’t refresh, or Cortana doesn’t respond. Thankfully, Microsoft’s Start Menu Repair Tool is here to help, and it’s free: startmenu.diagcab

After downloading, you can just doubleclick on the file and it will start the troubleshooter.
In my case it corrected the tiles database

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You notice your start menu button is no longer responding
When you decide to do a restart or sign out you get:

Task Host Window
microsoft\windows\plug and play\device install reboot required

there is a temporary solution: log out as user, kill the Task host windows and log in again. Startmenu works again !
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