CHKDSK + Checking Disk Space
     Reports disk size, space available, and RAM available. Also 
reports and optionally corrects internal disk errors.
    VERSION
          PC-DOS 2.0+ (revised from 1.0)
	  MS-DOS equivalent: CHKDSK (2.0+, revised from 1.0)
    TYPE
          External 
    SYNTAX
	  [d:][path] CHKDSK [cd:][cpath][cfilename][V]
    OPTIONS
	  [d:][path]		   Specifies the drive letter and
                                   path name containing the 
                                   CHKDSK command file.
	  [cd:][cpath][cfilename]  Specifies the file or files
                                   (if wildcards are used) to be 
                                   checked. If omitted, all files 
                                   in the current directory are 
                                   checked.
          /F                       Fixes errors in the File 
                                   Allocation Table (FAT).
          /V                       Provides file names as it 
                                   examines them so that you can 
                                   see where errors occur.
     CHKDSK is often used to verify the internal organization of 
a disk or to check the amount of space available. It can also be 
used to test for fragmented files. With the /F option, CHKDSK can 
be used to repair common internal disk errors.
    EXAMPLES
	  CHKDSK
checks drive C, reporting any internal errors as well as disk 
size, free space, and available RAM.
	  CHKDSK B:/F
checks the disk in drive B while fixing any internal errors it 
finds. You will be asked whether you wish to recover any lost 
data sectors (allocation units) into data files. If you respond 
Y, each lost allocation unit is recovered into its own file, 
named FILEnnn.CHK. You can inspect the recovered units by using
the TYPE or DEBUG command. If they are needed, you can RENAME 
them again or concatenate them using COPY; if not, you can delete 
them.
	  CHKDSK B:REPORTS
checks the file named REPORTS, reporting any noncontiguous areas 
on the disk that are occupied by the REPORTS file. The more 
noncontiguous areas CHKDSK reports, the greater the fragmentation 
on the disk, which reduces disk operation speed. To eliminate 
fragmentation, issue the BACKUP, FORMAT, and RESTORE commands to 
back up the disk, reformat it, and then restore the backed-up 
files to the disk, respectively.
	  CHKDSK B:V
checks the disk in drive B, repairing it while displaying a 
series of messages indicating its progress and status.
    MESSAGES
	  All specified file(s) are contiguous
The files you specified are not fragmented (that is, they are not 
stored in noncontiguous areas).
	  Cannot CHKDSK a network drive
You cannot use CHKDSK to check a network drive or a disk that is 
being shared on a network. If the disk is shared, have the server 
pause and then perform CHKDSK.
	  Cannot CHKDSK a SUBSTed or ASSIGNed drive
The SUBST command hides information that CHKDSK needs. Remove the 
substitution and try again.
	  CHDIR..failed, trying alternate method
CHKDSK could not change directories. Restart DOS and issue CHKDSK 
again.
	  Convert lost chains to files (Y/N)?
Respond Y to convert lost data blocks to files. If you have used 
the /F option, each chain will be recovered into a separate file. 
If you enter N, CHKDSK frees the blocks so that they can be 
allocated to new files.
	  Directory is joined,
	  tree past this point not processed.
The JOIN command has been used to join the drive to another 
device. CHKDSK skips over joined devices.
	  Directory to file (Y/N)?
The directory that is being checked contains too much invalid 
information to continue to be used as a directory. Enter Y to 
convert the directory to a file that can be examined with DEBUG. 
Enter N if you do not want the directory to be changed to a file.
	  Disk error reading/writing FAT x
The x portion of the FAT could not be updated. If this message
appears twice for FATs 1 and 2, format the disk. If FORMAT fails, 
the disk is probably unusable.
	  [.].Entry has a bad attribute
	  (or size or link)
One period preceding this message indicates that the current 
directory is in error; two periods indicates the parent 
directory. Use the /F option to correct the error.
	  Error found, F parameter not specified
	  Corrections will not be written to disk
CHKDSK is analyzing but not correcting the disk. To correct the 
disk, use the /F option.
	  File is cross-linked
	  on cluster xx
The same data block is linked to two different files.
	  filename Allocation error for file, size adjusted
The file allocation table contains an invalid file allocation 
unit. The file is truncated after the last valid file allocation 
unit.
	  filename Contains invalid cluster
	  [file truncated]
The file has an invalid pointer. If you have used the /F option, 
the bracketed message is also reported.
	  filename Contains xxx non-contiguous blocks
The reported number of noncontiguous areas were found for that 
file.
	  filename File cluster number is invalid
	  [, entry truncated]
The file contains an invalid pointer. If you have used the /F 
option, the file will be truncated and the bracketed message will 
appear.
	  Insufficient room in root directory
	  Erase files from root and repeat CHKDSK
There is not enough room to convert lost blocks to files.
	  Invalid current directory
An unrecoverable read error was located on the disk; no action is 
required.
	  path Convert directory to file (Y/N)?
The directory has been determined to no longer be usable. Respond 
Y to convert it to a file.
	  path Invalid subdirectory
The subdirectory contains invalid information. CHKDSK attempts to 
correct the error. Use the /V option for more information.
	  Probable non-DOS disk.
	  Continue (Y/N)?
Either the disk being checked is not formatted properly or it is 
badly damaged. If you have not specified the /F option, 
responding Y tells CHKDSK to indicate corrective actions but not 
to perform them.
	  Processing cannot continue,
This message is followed by another message that indicates the 
reason CHKDSK is unable to continue.
	  Tree past this point not
	  processed
Track 0 on the disk is bad, so the path past the directory that 
is currently being checked could not continue.
	  Unrecoverable error on directory
An error was encountered in the directory; no action is required.
	  xxxxxxxxx bytes disk space freed
The indicated number of bytes of disk space was not allocated and 
therefore was freed.
	  xxx lost clusters found in yyy chains
The indicated number of lost data blocks were not associated with 
any file.
    NOTE
     Running CHKDSK with the /F option can result in losing some 
information, so you should first run CHKDSK without the /F 
option. If CHKDSK reports errors, use the COPY command to copy 
the files off the disk as backup; then run CHKDSK /F. If you 
specify a file name or use the wildcard pattern *.*, CHKDSK 
reports the number of noncontiguous areas that the file(s) occupy 
on the disk. Version 1.0 of the command did not report available 
disk space, hidden files, user files, and bad sectors. It 
automatically ran with the /F option, fixing the disk while 
checking it.
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		  [For related topics, press R]
    SEE ALSO
          ASSIGN Command
          BACKUP Command
          CHDIR Command
          COPY Command
          FORMAT Command
          LABEL Command
          SELECT Command
          SUBST Command
          SYS Command
          TYPE Command
          VER Command
          VOL Command


Questions:

• SPAMthelamberts at SPAMnexicom.net asks: " During a chkdsk of a Fat32 system, I converted a directory to a file by mistake.
  Is there any way to get the directory back?
  
  Thanks" +

  .