CHKDSK: Checks a disk and displays a status report.

The `CHKDSK` command in the Windows Command Prompt is used to check the integrity of the file system on a drive and troubleshoot if necessary. Here are some examples with comments: Example 1: Simple file system check on drive C: without troubleshooting:

CHKDSK C:

Description: This command checks the file system on drive C for errors without automatically fixing them. Example 2: Checking the file system on drive D: with automatic error recovery:

CHKDSK D: /F

Description: This checks the file system on drive D: and automatically tries to fix any errors found. The switch `/F` stands for “Fix”. Example 3: Checking the file system on drive E: and recovering damaged sectors:

CHKDSK E: /R

Description: This command performs a comprehensive scan of the file system on drive E: and attempts to recover damaged sectors. The switch `/R` stands for “Recover”. Example 4: Checking all drives with automatic troubleshooting:

CHKDSK /F

Description: This checks the file system of all drives and automatically fixes any errors found. Example 5: Checking the file system on drive F: and logging the results to a text file:

CHKDSK F: /F /V > CHKDSK_Results.txt

Description: This command checks the file system on drive F:, attempts to fix any errors found, and logs the results to a text file named "CHKDSK_Results.txt". The `/V` switch stands for “Verbose” and outputs detailed information. Example 6: Scheduling a scan on next reboot for drive G: with automatic troubleshooting:

CHKDSK G: /F /R /X

Description: This command schedules a check of the file system on drive G: on the next reboot. The `/R` switch stands for Recover, `/F` means `Fix`, and `/X` forces the drive to be unmounted before checking. Note that when using `CHKDSK` on the drive where the operating system is installed, there may be a reboot requirement as the file system cannot be used during the scan. It is recommended to schedule the scan and reboot when the drive is not in use.

Microsoft Windows [Version 10.0.19045.3693]
(c) Copyright 1985-2023 Microsoft Corp.

C:\\WINDOWS>

Checks a disk and displays a status report.


CHKDSK [volume[[path]filename]]] [/F] [/V] [/R] [/X] [/I] [/C] [/L[:size]]


  volume          Specifies the drive letter (followed by a colon),
                  mount point, or volume name.
  filename        FAT/FAT32 only: Specifies the files to check for 
fragmentation.
  /F              Fixes errors on the disk.
  /V              On FAT/FAT32: Displays the full path and name of every file
                  on the disk.
                  On NTFS: Displays cleanup messages if any.
  /R              Locates bad sectors and recovers readable information
                  (implies /F).
  /L:size         NTFS only:  Changes the log file size to the specified number
                  of kilobytes.  If size is not specified, displays current
                  size.
  /X              Forces the volume to dismount first if necessary.
                  All opened handles to the volume would then be invalid
                  (implies /F).
  /I              NTFS only: Performs a less vigorous check of index entries.
  /C              NTFS only: Skips checking of cycles within the folder
                  structure.

The /I or /C switch reduces the amount of time required to run Chkdsk by
skipping certain checks of the volume.

There are a few important points to note when using the `CHKDSK` command in the Windows Command Prompt: 1. Admin Privileges: Administrator privileges are required to run `CHKDSK` on a drive. Make sure you open Command Prompt as an administrator. 2. Drive Lock: `CHKDSK` normally requires that the drive on which it is running is not in use. If you want to use `CHKDSK` for the system drive (typically C: drive), it may be necessary to schedule a scan on the next reboot, as the drive may not be active during the scan. 3. Scheduling the scan on next reboot: If you are running `CHKDSK` on the system drive or the drive is in use, you may need to schedule a scan on the next reboot. This can be achieved by invoking the `CHKDSK` command with the necessary switches.

   CHKDSK C: /F /R /X
   

Here, `/F` stands for Fix, `/R` stands for Recover, and `/X` forces the drive to be unmounted before checking. 4. Scan Time: The time it takes for `CHKDSK` to scan a drive may vary depending on the size of the drive and the level of fragmentation. It may take some time, especially if damaged sectors need to be recovered. 5. Data Backup: It is advisable to backup important data on the drive before running `CHKDSK`, especially if there are signs of hard drive problems. Although `CHKDSK` is designed to troubleshoot errors, there is always a small risk that data may be lost during the process. 6. Available Disk Space: Make sure there is enough free disk space on the drive running `CHKDSK`. The command can create temporary files and requires disk space to fix any errors found. 7. Error Logging: `CHKDSK` normally logs its results in Windows Event Viewer. After the process completes, check Event Viewer to see if any problems were identified and resolved. 8. Use of `/L` switch: In some cases, especially when there are file system issues, using the `/L` switch may be useful to enable advanced logging.

   CHKDSK C: /F /R /X /L:C:\CHKDSK_Log.txt
   

Here the logging is written to a text file called "CHKDSK_Log.txt" on the C: drive. Consider these points to ensure that `CHKDSK` is used effectively and safely on your system. If you are unsure or when critical data is involved, it is always advisable to consult a professional or Microsoft documentation.