My Lenovo G770 Laptop with I7 processor and 1 Tb SSD failed to install any Windows 10 updates since around Oct/Nov last year. I would get notifications about available updates, gone through the downloading ritual, only got everything reverted back to the original condition upon rebooting. There was some sort of kb??? error associtated with it but following all the trouble shooting steps led to nowhere.
Here is how I got it fixed. I downloaded the latest free Windows 10 upgrade from Microsoft. Made a bootable image on a usb stick (or dvd). I ran the setup from Windows 10 (not booting into the usb) for upgrading Windows 10. Within 30 minutes, all (new Windows 10, MS Office, drivers) updates were installed. No change to my settings, all installed software intact. If you are stuck with some sort of Windows update issues, give this a try. I think it is quite safe but do it at your own risk.