What error message do you get when the sfc /scannow fails to complete ?
Can you perform a chkdsk /r
If that completes then go into Event Viewer - ensure Event Viewer (Local) is highlighted in the left pane - if it isn't then just click on it.
When it has read the data expand Windows Logs - click on Application and look for a Wininit event.
Click on that then read the chkdsk log in the scrollable pane below.
As well as anything else it reports, look to see if it reports any KBs in bad sectors.
Else these cmds may help.
dism /online /cleanup-image /checkhealth
If that says the volume is repairable then enter -
dism /online /cleanup-image /restorehealth
and follow that with a sfc /scannow to see if it will complete.
The next step would be to perform a repair install which doesn't affect your personal stuff or installed programs.
You can create Win 10 install media by going to and reading the instructions at
https://www.microsoft.com/en-gb/software-download/windows10The procedure differs for DVD and USB.
To perform the repair install, open Windows Explorer - This PC - insert the install disk or USB then double click on its drive.
This will start the process if using a DVD but will open to its files if using an USB, in which case you will need to double click on setup Application.
This takes about 3hrs on my Win 10 machines.
I sometimes have to change my default browser back to IE and pin it back onto the taskbar, reset my Realtek HD Audio Manager and reinstall my Win 7 wireless adapter because it's more stable than the default 31 March 2016 one that gets installed.
I also have to reset WMP and Adobe Reader as my default apps.
Even if the /restorehealth cmd resolves, it's still worth creating install media.
