Microsoft DOS mscdex command
Mscdex is a CD-ROM "redirector" that enables CD-ROM access from the MS-DOS.
The mscdex or mscdexnt commands are external commands that are available in the below versions of Microsoft operating systems as mscdex.exe or mscdexnt.exe.
Syntax: MSCDEX.EXE /D:x /M:n /E /V /L:x /S /K
|/D:Device name||Allows you to specify the name for the driver. This must be identical to the device name in the Config.sys file. Usually MSCD0001 is commonly used.|
|/M:<n>||Specifies the number of sector buffers to cache the path table of a CD-ROM disk. Typically, each drive should have four to five buffers. The larger this number is, the less your computer will read directly from the CD-ROM drive.|
|/E||Tells MSCDEX.exe to use expanded memory.|
|/V||Displays information on memory usage when you boot your PC.|
|/L:<drive letter>||Specifies the letter you wan to assign the first CD-ROM drive. Such as D:|
|/S||Allows the CD-ROM to be shared on MS-NET based systems.|
|/K (Japanese)||Tells MSCDEX.EXE to use any KANJI file structures, if present rather than the default of alphanumeric file structures.|
When loading the MSCDEX line in Windows 3.x make sure to define the LASTDRIVE= statement with a line similar to "LASTDRIVE=Z" line.
Below is an example of how the MSCDEX line should look in your autoexec.bat:
LH C:\WINDOWS\COMMAND\MSCDEX.EXE /D:MSCD001
Remember that the above example, if used, must have the same device driver name as the CD-ROM driver in the config.sys.
- Additional information about the autoexec.bat and config.sys can be found on our autoexec.bat and config.sys page.
- Additional information about loading MS-DOS CD-ROM drivers can be found on our CD-ROM drivers page.
Errors and issues
When booting I receive message "MSCDEX is already running" and if I continue, all programs will stop running.
It is likely that you have more than one MSCDEX statement in your autoexec.bat. Edit the autoexec.bat and place a REM in front of one of the MSCDEX lines in the autoexec.bat. Additional information about editing the autoexec.bat can be found on our autoexec.bat and config.sys page.