SCANDISK

Starts Microsoft ScanDisk, a disk analysis and repair tool that checks a
drive for errors and corrects any problems that it finds. For an
introduction to using ScanDisk, see <An Introduction to ScanDisk>.

Syntax

To check the current drive for disk errors, use the following syntax:

    SCANDISK

To check one or more drives for disk errors, use the following syntax:

    SCANDISK [drive: [drive: ...]|/ALL] [/CHECKONLY | /AUTOFIX [/NOSAVE] |
    /CUSTOM] [/SURFACE] [/MONO] [/NOSUMMARY]

To check an unmounted compressed volume file for errors, use the following
syntax:

    SCANDISK volume-name [/CHECKONLY | /AUTOFIX [/NOSAVE] | /CUSTOM] [/MONO]
    [/NOSUMMARY]

To check a file or files for fragmentation, use the following syntax:

    SCANDISK /FRAGMENT [drive:][path]filename

To undo repairs you made previously, use the following syntax:

    SCANDISK /UNDO [undo-drive:] [/MONO]

Parameters

drive:
    Specifies the drive or drives you want to check and repair.

volume-name
    Specifies the name of the unmounted compressed volume file you want to
    check and repair. The volume-name parameter should take the form
    [drive:\]DRVSPACE.nnn, in which drive specifies the drive that contains
    the volume file and nnn specifies the extension of the volume file. For
    example, H:\DRVSPACE.000.

[drive:][path]filename
    Specifies the file(s) you want to examine for fragmentation. You can
    also specify wildcards for the filename.

undo-drive:
    Specifies the drive containing the Undo disk.

Switches

/ALL
    Checks and repairs all local drives.

/AUTOFIX
    Fixes damage without prompting you first. By default, if you start
    ScanDisk with the /AUTOFIX switch and ScanDisk finds lost clusters on
    your drive, it saves the lost clusters as files in the drive's root
    directory. To have ScanDisk delete lost clusters rather than saving
    them, include the /NOSAVE switch. (If you use the /AUTOFIX switch and
    ScanDisk finds errors, it still prompts you for an Undo disk; to prevent
    this, include the /NOSUMMARY switch.) You cannot use the /AUTOFIX switch
    in conjunction with the /CHECKONLY or /CUSTOM  switches.

/CHECKONLY
    Checks a drive for errors, but does not repair any damage. You cannot
    use this switch with the /AUTOFIX or /CUSTOM switches.

/CUSTOM
    Runs ScanDisk using the configuration settings in the [Custom] section
    of the SCANDISK.INI file. This switch is especially useful for running
    ScanDisk from a batch program. You cannot use this switch in conjunction
    with the /AUTOFIX or /CHECKONLY switches.

/MONO
    Configures ScanDisk to use a monochrome display. Instead of specifying
    this switch every time you run ScanDisk, you can include the
    DISPLAY=MONO line in your SCANDISK.INI file.

/NOSAVE
    Directs ScanDisk to delete any lost clusters it finds. Can be used only
    in conjunction with the /AUTOFIX switch. (If you start ScanDisk with the
    /AUTOFIX switch and omit the /NOSAVE switch, ScanDisk saves the contents
    of any lost clusters as files in the root directory of the drive.)

/NOSUMMARY
    Prevents ScanDisk from displaying a full-screen summary after checking
    each drive. (This switch also prevents ScanDisk from prompting you for
    an Undo disk if it finds errors.)

/SURFACE
    Automatically performs a surface scan after checking other areas of a
    drive. During a surface scan of an uncompressed drive, ScanDisk confirms
    that data can be reliably written and read from the drive being scanned.
    During a surface scan of a compressed drive, ScanDisk confirms that data
    can be decompressed. You should periodically do surface scans of all
    drives.

    By default, when it has finished checking a drive's file system,
    ScanDisk asks whether or not you want to perform a surface scan.
    However, if you specify the /SURFACE switch, ScanDisk proceeds with the
    surface scan without prompting you first. When /SURFACE is used in
    conjunction with the /CUSTOM switch, it overrides the Surface setting in
    the [Custom] section of the SCANDISK.INI file.