All External Command of MS-Dos.

External command
A MS-DOS command that is not included in command.com. External commands are commonly external either because they require large requirements or are not commonly used commands. Below are examples of MS-DOS and Windows command line external commands currently listed in the Computer Hope database.

Many of the external commands are located in the Windows\system32 or Winnt\system32 directories. If you need to locate the external file in order to delete it, rename it or replace it, you can also find the file through MS-DOS
 
Some external DOS command
CHKDSK:-
This command is used to check for error on disk drive.
Syntax: C:\>chkdsk


Format:-
This command is used to format for disk drive
Syntax: C:\>format drive name
Eg, C:\>forma d:/q


Attrib:-
This command is used to change the attributes of file and folder.
-To make file or folder hidden
C:\>Attrib <file or folder name> +h
Eg, C:\>attrib hari.doc +h
-To show hidden file and folder
C:\>attrib <file or folder name> -h
Eg, attrib hari.doc –h
Hole file hidden
Eg, c:\>attrib +r +a +s +h
Hole hidden file show
Eg, C:\>attrib –r –a –s –h

Edit:-
This command is used to edit for file.
Syntax: C:\>edit file name
Eg, C:\>edit ram.doc
Shutdown:-
This command is used to shutdown, restart, logoff the computer.
Shutdown
C:\>shutdown –s –t 60 –c “comment”
Restart
C:\>shutdown –r –t -60
Logoff
C:\>shutdown –L
Net user:-
This command is used to create a new user account.
Syntax: C:\>net user <user name> <password> /add
Eg, C:\>net user hari 12345 /add