chkdsk command

What Is CHKDSK

CHKDSK is a command that can be run in Command Prompt to verify the logical integrity of the file system. The full name of CHKDSK is actually checkdisk; as the name suggests, it is designed to check disk for errors and then fix it. CHKDSK works on the basis of certain partition file system to create and display the disk status. If CHKDSK is typed without any parameters, the disk status in the current drive will be displayed to people.

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C:\Users\somet>chkdsk /?

Checks a disk and displays a status report.

CHKDSK [volume[[path]filename]]] [/F] [/V] [/R] [/X] [/I] [/C] [/L[:size]] [/B] [/scan] [/spotfix]

  volume              Specifies the drive letter (followed by a colon),

                      mount point, or volume name.

  filename            FAT/FAT32 only: Specifies the files to check for

                      fragmentation.

  /F                  Fixes errors on the disk.

  /V                  On FAT/FAT32: Displays the full path and name of every

                      file on the disk.

                      On NTFS: Displays cleanup messages if any.

  /R                  Locates bad sectors and recovers readable information

                      (implies /F, when /scan not specified).

  /L:size             NTFS only:  Changes the log file size to the specified

                      number of kilobytes.  If size is not specified, displays

                      current size.

  /X                  Forces the volume to dismount first if necessary.

                      All opened handles to the volume would then be invalid

                      (implies /F).

  /I                  NTFS only: Performs a less vigorous check of index

                      entries.

  /C                  NTFS only: Skips checking of cycles within the folder

                      structure.

  /B                  NTFS only: Re-evaluates bad clusters on the volume

                      (implies /R)

  /scan               NTFS only: Runs an online scan on the volume

  /forceofflinefix    NTFS only: (Must be used with "/scan")

                      Bypass all online repair; all defects found

                      are queued for offline repair (i.e. "chkdsk /spotfix").

  /perf               NTFS only: (Must be used with "/scan")

                      Uses more system resources to complete a scan as fast as

                      possible. This may have a negative performance impact on

                      other tasks running on the system.

  /spotfix            NTFS only: Runs spot fixing on the volume

  /sdcleanup          NTFS only: Garbage collect unneeded security descriptor

                      data (implies /F).

  /offlinescanandfix  Runs an offline scan and fix on the volume.

  /freeorphanedchains FAT/FAT32/exFAT only: Frees any orphaned cluster chains

                      instead of recovering their contents.

  /markclean          FAT/FAT32/exFAT only: Marks the volume clean if no

                      corruption was detected, even if /F was not specified.

The /I or /C switch reduces the amount of time required to run Chkdsk by

skipping certain checks of the volume.