Syntax
      CHKNTFS drive: [...]
      CHKNTFS /C drive: [...]
      CHKNTFS /X drive: [...]
      CHKNTFS /t[:Time]
      CHKNTFS /D

Key
   drive : Specifies a drive letter.

   /C : Check - schedules chkdsk to be run at the next reboot.

   /X : Exclude a drive from the default boot-time check. 
        Excluded drives are not accumulated between command invocations.

   /T : Change the Autochk.exe initiation countdown time (time in seconds)
        If you don't specify Time: displays the current countdown time.

   /D : Restore the machine to the default behavior; all drives are
        checked at boot time and chkdsk is run on those that are dirty.
        This undoes the effect of the /X option.

If no switches are specified, CHKNTFS will display the status of the dirty bit for each drive.

/T option is new in Win XP