I'm mad at Microsoft for forcing Windows 7 down my mother's throat. As my mother isn't very tech-savvy, I put the updates on automatic. When Windows 10 was offered, I marked the GWX update as hidden. However, MS put it on the recommended list, so on the 19th of December it came back (I know from the update log) and installed automatically. My mother was nagged by Windows wanting to upgrade and clicked 'later' apparently, but it kept nagging her. The day after Christmas Windows 10 was downloading to install itself. I deleted the _WindowsBT folder, deinstalled the notorious GWX update, used disc cleanup to clean clean system files->cleanup Update, removed the tick at Upgrade to Windows 10 and restarted - the tick is back. I looked for help by googling how to cancel a Windows 10 install and apparently I passed the point of no return - after each removal of the update and cancelling of the install, the Windows Update screen says "ready to install Windows 10", superimposed on any other updates.
I made a clean install of Windows, making use of the moment to get my mother a (legal) Dutch version instead of the (legal) English version that was on her PC before, so she can read the warnings better. Frustration didn't stop there, as after a clean install, Windows Update kept hanging and after much trying to troubleshoot it, I just left it running the whole night and in the morning at last the 152 critical updates were found and downloaded. The remaining 63 recommended and optional updates that I sifted through by hand to keep clean of Windows 10, took another half a day.
All in all I stayed at my parents a full day longer just to sort out computer problems.
akwater: So....
I've got cancer.
Sorry, my problems are just a minor nuisance compared to the bad news you've got - and I suck at giving people advice, but I wish you much strength in the days, months and hopefully years to come.