Modifying Default Bootup Run of CHKDSK /F

The default behavior of Windows NT at boot-up is to check every NTFS partition for the presence of the "Dirty Bit" and to run CHKDSK /F when the Dirty Bit has been set for this partition. Running CHKDSK /F takes a long time and permanently modifies the files on your system. You may want to delay the execution of CHKDSK /F for a short time while you attempt to retrieve some the file fragments. You can override the default behavior at boot-up with the CHKNTFS command utility. You can force or prevent the running of CHKDSK /F for any NTFS partition or restore the behavior again to its default. The relevant Registry entry is

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\BootExecute

Normally it is set to

autocheck autochk *

To prevent CHKDSK /F from running for NTFS partition D: the entry becomes:

autocheck autochk *
autocheck autochk /k:D

To force CHKDSK /F for drive D: when the Dirty Bit was not set the entry becomes

autocheck autochk *
autocheck autochk /m:D

The CHKNTFS utility is a much safer and easier method to modify the Registry entry. More information can be found in the CHKNTFS section in command line programs.