Mohammad's answer should more or less fix your problem, although I will note if it persists or worsens, it could be MBR or partition table problem, in which you could use software like Gparted to check to see if it is, and or possibly fix the problem.
This should fix the disk. Reboot after this.
I shall add, make sure your extension is the right one (you can find this on the original error message you got).
If it still doesn't work use a Live CD like Hiren's Boot CD mainly for DOS or there are a lot of others (here is a List of rescue n repair live CDs). Try the one you like. Hiren's Boot CD has chkdsk utility. System Rescue CD is another nice rescue CD.
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How to fix damaged NTFS partition?