6. The method of claim 1 , wherein calculating the total size of the volume comprises: analyzing the MFT entry corresponding to the metadata file; obtaining information of the metadata file using a real attribute size item of a non-resident attribute header of $DATA attributes of the MFT entry; and calculating a total number of sectors of the volume based on the information of the metadata file.
7. The method of claim 6 , wherein the metadata file is an undeleted metadata file from among a $Bitmap file corresponding to MFT entry #6, a dot (.) file corresponding to MFT entry #5, and a $BadClus file corresponding to MFT entry #8.