ChkDsk Process on NTFS Volumes

When you run ChkDsk on NTFS volumes, the ChkDsk process consists of three major stages and two optional stages. ChkDsk displays its progress for each stage with the following messages.

The following list describes each of the ChkDsk stages.

• Stage 1: ChkDsk verifies each file record segment in the Master File Table During stage 1, ChkDsk examines each file record segment in the volume's Master File Table (MFT). A specific file record segment in the MFT uniquely identifies every file and directory on an NTFS volume. The percentage complete that ChkDsk displays during this phase is the percentage of the MFT that has been verified.
  The percentage complete indicator advances relatively smoothly throughout this phase, although some unevenness might occur. For example, file record segments that are not in use require less time to process than do those that are in use, and larger security descriptors take more time to process than do smaller ones. Overall, the percentage complete indicator is a fairly accurate representation of the actual time required for that phase.
• Stage 2: ChkDsk checks the directories in the volume During stage 2, ChkDsk examines each of the indexes (directories) on the volume for internal consistency and verifies that every file and directory represented by a file record segment in the MFT is referenced by at least one directory. ChkDsk also confirms that every file or subdirectory referenced in each directory actually exists as a valid file record segment in the MFT and checks for circular directory references. ChkDsk then confirms that the timestamps and the file size information associated with files are up to date in the directory listings for those files.
  The percentage complete that ChkDsk displays during this phase is the percentage of the total number of files on the volume that are checked. For volumes with many thousands of files and folders, the time required to complete this stage can be significant.
  The duration of stage 2 varies because the amount of time required to process a directory is closely tied to the number of files or subdirectories listed in that directory. Because of this dependency, the percentage complete indicator might not advance smoothly during stage 2, though the indicator continues to advance even for large directories. Therefore, do not use the percentage complete indicator as a reliable representation of the actual time remaining for this phase.
• Stage 3: ChkDsk verifies the security descriptors for each volume During stage 3, ChkDsk examines each of the security descriptors associated with each file and directory on the volume by verifying that each security descriptor structure is well formed and internally consistent. The percentage complete that ChkDsk displays during this phase is the percentage of the number of files and directories on the volume that are checked.
  The percentage complete indicator advances relatively smoothly throughout this phase, although some unevenness might occur.
• Stage 4: ChkDsk verifies file data During stage 4 (which is optional), ChkDsk verifies all clusters in use. ChkDsk performs stages 4 and 5 if you specify the /r parameter when you run ChkDsk. The /r parameter confirms that the sectors in each cluster are usable. Specifying the /r parameter is usually not necessary, because NTFS identifies and remaps bad sectors during the course of normal operations, but you can use the /r parameter if you suspect the disk has bad sectors.
  The percentage complete that ChkDsk displays during stage 4 is based on the percentage of used clusters that are checked. Used clusters typically take longer to check than unused clusters, so stage 4 lasts longer than stage 5 on a volume with equal numbers of used and unused clusters. For a volume with mostly unused clusters, stage 5 takes longer than stage 4.
• Stage 5: ChkDsk verifies free space During stage 5 (which is optional), ChkDsk verifies unused clusters. ChkDsk performs stage 5 only if you specify the /r parameter when you run ChkDsk. The percentage complete that ChkDsk displays during stage 5 is the percentage of unused clusters that are checked.