Which version of Win 10 are you on?
right click start button
choose run...
type
winver and press enter - the version you are on may matter later
right click start button
choose command prompt (admin)
copy/paste this into window - it needs to be exact
DISM /Online /Cleanup-Image /RestoreHealth and press enter
What DISM does is it cleans the image file that Reset uses to fix windows. Once its complete, run the next command in same window as it will fix the system files as well:
type
SFC /scannow and press enter
restart PC and then try the reset again
Now if DISM asks for a source file,
and you on version 1607, you need to do the next step.
If you aren't on 1607, see note below
Download a copy of the win 10 iso from
Here - create ISO by telling it you want to make DVD - and then mount that ISO in file explorer (see
Here) and then copy paste the below command into command prompt (admin)
DISM /Online /Cleanup-Image /RestoreHealth /source:WIM:X:\Sources\Install.wim:1 /LimitAccess
Where "X" is the drive letter where the ISO is located. Simply change the "X" to the correct drive letter
Note: you can't run the source command if you are aren't on 1607, as you need an ISO that matches version you are on and unless you lucky and have one, its a struggle to find and its easier to just upgrade to latest version of win 10 instead. To upgrade to current version, go to
here and press upgrade now - this will download the upgrade assistant which once run will upgrade win 10 to the current build... for a few more weeks until MS update it again