Let's try it another way - I don't know why you are getting O/N instead of Y/N
You could see what happens when you enter o but go Start - click on the Settings cog - Update & Security - Recovery - under Advanced start-up click on Restart now - Troubleshoot - Advanced options - Command Prompt - click on the computer name
Enter your password if one used then click on Continue or if no password is used then just click on Continue
Enter bcdedit |find "osdevice" and using whichever partition letter, enter chkdsk x: /r where x is the partition letter.
For clarity, that is a Pipe symbol before find and is the upper case of \
The bcdedit cmd is necessary as it doesn't always see the volume as being in C
This method doesn't require a reboot to dismount the volume as you are working outside of Windows and you will see its full report on screen.
This will take some time but disregard the error 50 at the end because that relates to it not being able to create a Wininit file in Event Viewer as it would normally do when this is performed normally from within Windows.
