• Skipping volume checks
  The /i or /c switch reduces the amount of time required to run chkdsk by skipping certain volume checks.
  
• Checking a locked drive at restart
  If you want chkdsk to correct disk errors, you cannot have open files on the drive. If files are open, the following error message appears:
  
  Chkdsk cannot run because the volume is in use by another process. Would you like to schedule this volume to be checked the next time the system restarts? (Y/N)

  If you choose to check the drive the next time you restart the computer, chkdsk checks the drive and corrects errors automatically when you restart the computer. If the drive partition is a boot partition, chkdsk automatically restarts the computer after it checks the drive.
  You can also use the chkntfs /c command to schedule the volume to be checked the next time the computer is restarted. Use the fsutil dirty set command to set the volume's dirty bit (indicating corruption), so that Windows runs chkdsk when the computer is restarted.
  
• Reporting disk errors
  You should use chkdsk occasionally on FAT and NTFS file systems to check for disk errors. Chkdsk examines disk space and disk use and provides a status report specific to each file system. The status report shows errors found in the file system. If you run chkdsk without the /f parameter on an active partition, it might report spurious errors because it cannot lock the drive.
  
• Fixing logical disk errors
  Chkdsk corrects logical disk errors only if you specify the /f parameter. Chkdsk must be able to lock the drive to correct errors.
  Because repairs on FAT file systems usually change a disk's file allocation table and sometimes cause a loss of data, chkdsk might display a confirmation message similar to the following:
  
  10 lost allocation units found in 3 chains.
  Convert lost chains to files?

  If you press Y, Windows saves each lost chain in the root directory as a file with a name in the format File<nnnn>.chk. When chkdsk finishes, you can check these files to see if they contain any data you need. If you press N, Windows fixes the disk, but it does not save the contents of the lost allocation units.
  If you do not use the /f parameter, chkdsk displays a message that the file needs to be fixed, but it does not fix any errors.
  If you use chkdsk /f on a very large disk or a disk with a very large number of files (for example, millions of files), chkdsk /f might take a long time to complete.
  
• Finding physical disk errors
  Use the /r parameter to find physical disk errors in the file system and attempt to recover data from any affected disk sectors.
  
• Using chkdsk with open files
  If you specify the /f parameter, chkdsk displays an error message if there are open files on the disk. If you do not specify the /f parameter and open files exist, chkdsk might report lost allocation units on the disk. This could happen if open files have not yet been recorded in the file allocation table. If chkdsk reports the loss of a large number of allocation units, consider repairing the disk.
  
• Using chkdsk with Shadow Copies for Shared Folders
  Because the Shadow Copies for Shared Folders source volume cannot be locked while Shadow Copies for Shared Folders is enabled, running chkdsk against the source volume might report false errors or cause chkdsk to unexpectedly quit. You can, however, check shadow copies for errors by running chkdsk in Read-only mode (without parameters) to check the Shadow Copies for Shared Folders storage volume.
  
• Understanding exit codes
  The following table lists the exit codes that chkdsk reports after it has finished.
  

   

  Exit code	Description
  0	No errors were found.
  1	Errors were found and fixed.
  2	Performed disk cleanup (such as garbage collection) or did not perform cleanup because /f was not specified.
  3	Could not check the disk, errors could not be fixed, or errors were not fixed because /f was not specified.

• The chkdsk command, with different parameters, is available from the Recovery Console.
  
• On servers that are infrequently restarted, you may want to use the chkntfs or the fsutil dirty query commands to determine whether the volume's dirty bit is already set before running chkdsk.
  

If you want to check the disk in drive D and have Windows fix errors, type:

chkdsk d: /f

If it encounters errors, chkdsk pauses and displays messages. Chkdsk finishes by displaying a report that lists the status of the disk. You cannot open any files on the specified drive until chkdsk finishes.

To check all files on a FAT disk in the current directory for noncontiguous blocks, type:

chkdsk *.*

Chkdsk displays a status report, and then lists the files that match the file specifications that have noncontiguous blocks.