The CONFIG.SYS file is a text file that contains special commands. These
commands configure your computer's hardware components so that MS-DOS and
applications can use them. When MS-DOS starts, it carries out the commands
in the CONFIG.SYS file. Typically, the CONFIG.SYS file is located in the
root directory of drive C.
The following CONFIG.SYS commands can be used only in the CONFIG.SYS file:
The following commands are commonly used in the CONFIG.SYS file and can also
be typed at the command prompt:
The following special CONFIG.SYS commands are used only to define multiple
configurations within the CONFIG.SYS file:
For more information about defining multiple configurations, see
Special characters in the CONFIG.SYS file
The CONFIG.SYS file can also contain the following special characters:
; Specifies that the current line is a descriptive comment
and should not be carried out. Insert this character at the
beginning of the line. (You can also insert a comment by using
the REM command.)
? Specifies that MS-DOS is to ask for confirmation before
carrying out the current command. Insert this character
immediately after the command you want to prompt for, without
any intervening spaces, but before the equal sign (=). For example,
to have MS-DOS ask for confirmation before carrying out the
DOS=HIGH command, you would change the command to read
DOS?=HIGH. To have MS-DOS ask for confirmation before
carrying out the DEVICEHIGH /L:1,7280=MYFILE.SYS
command, you would change the command to read as follows:
Bypassing CONFIG.SYS and AUTOEXEC.BAT commands
If you are having system problems that you suspect are caused by one or more
commands in your CONFIG.SYS or AUTOEXEC.BAT file, you might want to bypass
some or all the commands in these files. (For information about bypassing
DriveSpace, see the next paragraph).
* To bypass all the commands in your CONFIG.SYS and AUTOEXEC.BAT files,
press the F5 key immediately after starting your computer, when you see
the text "Starting MS-DOS...".
* To bypass individual CONFIG.SYS and AUTOEXEC.BAT commands, press the F8
key instead. MS-DOS will then prompt you to carry out or bypass each
command. To carry out all remaining startup commands, press ESC. To
bypass all remaining startup commands, press F5.
To disable this feature, add the <SWITCHES /N> command to your CONFIG.SYS
Starting your computer without loading DRVSPACE.BIN
DRVSPACE.BIN is the part of MS-DOS that provides access to DriveSpace
compressed drives. Normally, if your hard drive has been compressed using
DriveSpace, DRVSPACE.BIN is loaded even if you press F5 or F8. There are two
ways to disable this:
* To start your computer without loading DRVSPACE.BIN, and to bypass all
the commands in your CONFIG.SYS and AUTOEXEC.BAT files, press CTRL+F5.
* To start your computer without loading DRVSPACE.BIN, and to bypass
individual commands in your CONFIG.SYS & AUTOEXEC.BAT files, press
CTRL+F8. MS-DOS will then prompt you to carry out or bypass each
CONFIG.SYS and AUTOEXEC.BAT command. To carry out all remaining startup
commands, press ESC. To bypass all remaining startup commands, press F5.
Note: If you bypass DRVSPACE.BIN, you will not be able to gain access to
your DriveSpace compressed drives until you restart your computer
with DRVSPACE.BIN. (Your compressed drives will remain on your hard
disk as hidden files with names such as DRVSPACE.000. Do not delete
or rename such files.)
To disable this feature, use the <DRVSPACE /SWITCHES> command.
For more information about your CONFIG.SYS file, see the chapter
"Configuring Your System" in the MS-DOS User's Guide.
Edward Mendelson, wrote:
Is there a way of displaying a comment in config.sys similar to the
echo statement in batch files.
I'm looking for a way to add some information to the top/bottom of
the config.sys menu.
; This is a comment but:
set? a=This is a comment (works as "ECHO blah" and "PAUSE" in batch).