I don't allow the GWX.exe file to run , I have a pinned link to the systems Windows Task Manager which I click on as soon as my PC boots up , I select the gwx.exe file and stop it , now it is like a virus and will within ten minutes restart so it gets stopped again , now leave my pc on for a few hours and it will start again so again I just close it down.
It is like a virus in the way you can't remove it and MS should've been ordered to stop a long time ago , they are committing a criminal act of misuse of computers by forcing this on us without our permission ( there is around 7Gb of install data hidden on your HD by the time this pop up runs.... ) so I will never "upgrade" ( downgrade in my opinion ) to Windows 10 from Win7 Pro that I currently use.