If your Windows can not boot up and you think the NTFS volume was damaged by Windows or some other way and it cannot be mounted.You can try ntfsfix command to fix this problem if you have a Ubuntu dual-boot system.
ntfsfix is a utility that fixes some common NTFS problems. ntfsfix is NOT a Linux version of chkdsk. It only repairs some fundamental NTFS inconsistencies,resets the NTFS journal file and schedules an NTFS consistency check for the first boot into Windows.
ntfsfix is part of the ntfsprogs package,so first we need install ntfsprogs:
sudo apt-get install ntfsprogs
then,run ntfsfix command on the ntfs volume:
sudo ntfsfix /dev/sda1
change “/dev/sda1″(without quotes) to your Windows partition name.