[Look] An Overview of CHKNTFS: Definition/Functions/Examples [MiniTool Wiki]
What Is chkntfs?
Chkntfs, also called check NTFS, is a kind of Windows command line that displays or modifies automatic disk checking when the computer is started. If it is used without extra options, chkntfs command displays the file system of the target partition/volume. If automatic file checking is scheduled to run, chkntfs displays whether the specified partition is dirty or is scheduled to be checked next time when the computer is booted up.
Chkntfs is an external command that is available in below Microsoft Windows operating systems as chkntfs.exe.
Chkntfs works by changing the registry key of BootExecute in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager. The default value of BootExecute is a REG_MULTI_SZ value of autocheck autochk*
CHKNTFS is also capable of disabling CHKDSK /F (check disk) if it is been set to run on the next reboot. This is helpful if you have scheduled a chkdsk at one point but need to reboot without chkdsk running at this time.
chkntfs <volume> [...]
chkntfs [/x <volume> [...]]
chkntfs [/c <volume> [...]]
Parameters of chkntfs
It specifies one or more partitions or volumes to check when the computer starts. A valid partition should include a driver letter that followed by a colon, a mount point, or a partition label/name.
This parameter restores all chkntfs default settings, except for the countdown time for automatic file checking. By default, all partitions are checked when the computer is booted up while chkdsk operates on those that are dirty.
This command alters the Autochk.exe initiation countdown time to the customized amount of time in seconds. If no time is typed in, /t will display the current countdown time.
/x <volume> [...]
This order defines one or more partitions to be excluded from checking when the machine is started, even if the volume is marked as requiring chkdsk.
/c <volume> [...]
This command line schedules one or more partitions to be checked when the computer is booted up and runs chkdsk on those ones that are dirty.
It displays help within the command prompt.
Some Examples of the chkntfs Command
The following will show you some easy examples of how to use the chkntfs commands in CMD.
Example 1. Display the file system for system C drive.
The identification of the filesystem type on the first line is fairly self-evident. “Not dirty” means that C drive was properly “cleaned up” the last time the system shut down. That is to say, the computer was shut down properly.
If the OS isn’t shut down properly, any drives in use, containing one or more files that are opening when the machine loses power, will be marked “dirty”. The dirty bit is a flag that indicates that there is still data to be written to the target drive. Those drives will be scanned the next time when Windows boots up.
If automatic file checking is scheduled to run, additional output will display including whether the drive is dirty or has been manually scheduled to be checked the next time the computer is turned on.
Example 2. Change the Autochk.exe initiation countdown time to 90 seconds.
Of course, you are able to set the Autochk.exe initiation countdown time to 0 second. Yet, if you do that, you are unable to cancel a potentially time-consuming automatic file check.
Example 3. Exclude volume E and F from being checked
chkntfs /x e: f:
You must list the multiple partitions within a single command. The /x command option is not accumulative. If you type it more than once, the most recent entry overrides the previous entry.
Example 4. Schedule automatic file checking on drive E instead of drive C and D.
chkntfs /x c: d: e:
chkntfs /c e:
The /c command-line option is accumulative. If you type /c more than once, each entry remains. To make sure that only a particular volume is checked, you need to reset to the default settings to clear all previous commands in the first place. Then, exclude all partitions from being checked. Finally, schedule automatic file checking for the target volume.
For checking partition/volume filesystem, besides chkntfs commands, you can also rely on a third-party program called MiniTool Partition Wizard, which enables you to easily check file systems of your volumes with graphic guide.
Chkntfs Related Contents
Some malware camouflages itself as chkntfs.exe, especially for those viruses that locate in the C:\Program Files or C:\Windows folder. There are some examples of such trojans like TrojanDownloader:Win32/Carberp.C or TrojanDownloader:Win32/Carberp.E (detected by Microsoft) and TROJ_BAMITAL.SMH or TROJ_LAMEWAR.VTG (detected by TrendMicro).
Therefore, you need to protect your computer from virus attacks with a Windows security firewall and antivirus or rely on third-party programs. And, you are also recommended to avoid data loss by backing up important files/folders with professional tools like MiniTool ShadowMaker.