My 'upgrade' to win 10 on a brand new unused Lenovo PC processed very easily and seemed to work fine for nearly a day
until I noticed it was failing to restart after some software and driver updates.
Then after repeated attepmts to update some intel drivers for Win 10 after 'Lenovo Companion' stated they were necessary,
Restart failed completely, and never worked again..

That's why I rolled back to Win 8.1.
But restart still failed to work.

So resorted to lenovo onekey recovery back to factory reset.

Now it functions fine in win 8.1, but when I tried to create a recovery drive,
I get a message stating components are missing and I need the Windows 8.1 install disc,
which of course the manufacturer does not supply.....😫