If you have a disk that has been uncleanly unmounted, you can run a tool called ntfsfix to correct the issues. Keep in mind that ntfsfix is a utility that fixes some common NTFS problems, but it is not a Linux version chkdsk or equivalent of fsck. It will repair some basic inconsistencies and reset the NTFS journal. You should repair NTFS disks under windows, when possible.

Running the command:

 ntfsfix /dev/sdc1

(where sdc1 is the windows partition). 

If you don't have that command, you most likely need to install the package: ntfsprogs. 

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