Updated: April 17, 2012
Applies To: Windows 7, Windows Server 2000, Windows Server 2003, Windows Server 2003 R2, Windows Server 2008, Windows Server 2008 R2, Windows Server 2008 R2 with SP1, Windows Vista, Windows XP
Runs when the computer is started and prior to Windows Server® 2008 R2 starting to verify the logical integrity of a file system.
Autochk.exe is a version of Chkdsk that runs only on NTFS disks and only before Windows Server 2008 R2 starts. Autochk cannot be run directly from the command-line. Instead, Autochk runs in the following situations:
If you try to run Chkdsk on the boot volume
If Chkdsk cannot gain exclusive use of the volume
If the volume is flagged as dirty
Warning The Autochk command-line tool cannot be directly run from the command-line. Instead, use the Chkntfs command-line tool to configure the way you want Autochk to run at startup.
You can use Chkntfs with the /x parameter to prevent Autochk from running on a specific volume or multiple volumes.
Use the Chkntfs.exe command-line tool with the /t parameter to change the Autochk delay from 0 seconds to up to 3 days (259,200 seconds). However, a long delay means that the computer does not start until the time elapses or until you press a key to cancel Autochk.