Getting the CD ROM to work in Dos

[Kathye]

I have a very old notebook computer that can no longer get into windows (registry errors). I'd like to reinstall my Windows 95 CD onto this computer to give it chance to repair this and various other errors. I can't just re boot because this system only supports either floppy or CD ROM, not both at the same time.

However, I've been tearing my hair out trying to get the syntax right in the commands to get my CD ROM drive recognised from DOS. I've found quite a lot of helpful sites on the net to get me started but the end result of all my attempts to edit config.sys autoexec.bat or dosstart.bat to match the websites is still a dead computer.

My CD ROM is of a type that will run with MSCDEX so that isn't the problem.

Please could anyone give me any advice on the best way to proceed?

My CD ROM is a TEAC CD 46E but when I opened the autoexec.bat it recommended the following settings for making MSCDEX to work;

"Run Dosstart to load MSCDEX and REAL mouse. The string following /D: must match that in the config.sys

MSCDEX.EXE /D:OEMCD001 /L:d"

Well, when I try to do this and match it with the config.sys the best result I had so far was an error message saying

"usage: MSCDEX [/E/K/S/V][/D:<driver>...][/L:<letter>][m:<buffers>]"

Would anyone be able to help me translate my parameters into the above syntax given that I do not know what EKS and V are? And comparing this syntax with that given in the autoexec.bat the OEMCD001 is in the wrong place there, it's in the driver's part of the sentence?

Please forgive my fumbling attempts to get to grips with this. I've not much hope of getting technical support from Gateway who supplied the notebook and TEAC though wonderfully helpful to the best they could be are not actually supposed to help at all with internal CD ROM drives so I really am on my own with this.

Thanks

Kathy

[Sylvander]

Hello Kathye

First things first:
Have you tried entering the command "scanreg /restore" at the dos prompt to restore a backup copy of an uncorrupted registry?
If one of the older of the five copies is good you'll get Widows working again, which is a good start.

Here's a document I made some time back:

To access CD-drive from :

A. “Command Prompt Only”

1. Reboot > hold ctrl ( in win98 ), or F8 ( in win 95 ),
Or [if “drive overlay software” is used to overcome outdated BIOS and gain use of large hard drive ] F8 ( in win 98 ).

2. Choose “Command Prompt Only” from the boot menu which appears.

3. At “C:\>” type “dosstart.bat” <enter> ( without the quotation marks )
[ This file is located at C:\windows\dosstart.bat , open it in wordpad if you’re curious.]

You now have DOS access to your CD-drive .

B. “Safe Mode”

1. Reboot ( as 1 above ).
2. As 2 above.
3. As 3 above.
4. At “C:\>” type “cd\windows” <enter>.
5. At “c:\windows>” type “win /d:m”<enter>.

The P.C. will now boot into “Safe mode with CD-drive access”.

c. “MS-DOS mode” ( This is designed to give access to CD-drives )

( You can only get to this from within windows. )

1. Boot into windows > “shut down” > “re-start in MS-DOS mode”.

The P.C. reboots and you have MS-DOS access to your CD-drive.


To create a win98 “startup disk” from “command prompt only”.

1. Go to “Command prompt only”. ( as A, 1, 2, above. )

2. Insert a blank, formatted floppy in “drive A”.

3. At “c:\>” type the following commands, pressing <enter> after each.

cd windows\command
smartdrv.exe
bootdisk a:

4. Follow the instructions on screen.


Notes on accessing CD-drives from DOS and Safe Mode.

1. Why would you want to do it anyway?
Because :

A. These are the safest (though slightly slower) ways of running (windows?) “setup.exe”, to install or reinstall or confirm an installation and eliminate corrupted or missing (windows?) files (you may have other reasons).

1. If windows was booting you could fall back to “MS-DOS mode”
(for a safer setup) or indeed any of the other methods.

2. If windows is not booting fall back to “Safe mode with CD-drive access”.

3 If not booting to “safe mode” fall back to “command prompt only” with CD-drive access.

4. You could access the CD-drive from a DOS prompt using the win98 “startup disk”

But what if you had forgotten to make one, or lost it, and windows was failing to boot so you couldn’t make one ( see the method above ); or the drivers on the disk were incompatible with your CD drive? Using the “startup disk” is always an option at any time but the other methods are available even when it is not.

5. If you decide to run “setup.exe” the easy way (from within windows) microsoft recommends :
That you use “ctrl + alt +del” repeatedly to close all but “Explorer.exe” and “systray.exe” in the “close program” window, since one or more programs may interfere with the activities of “setup.exe”.

Notes on C. “MS-DOS mode” (above)

1. When the P.C. reboots into MS-DOS mode, “config.sys” is read and a command line within it
Loads the “real mode” (16-bit) device driver supplied by the CD-drive OEM (Original Equipment Manufacturer). This is only true, of course, if the driver has been installed!

Next, “autoexec.bat” is read and a command line would load the windows driver “mscdex.exe”, this being the other partner, which links windows to the OEM CD-drive driver.
But wait! If windows 98 was installed, or indeed reinstalled, after this was in place it could, during installation, detect that your P.C. had a CD-drive for which it had a “safe mode” (32 bit) driver and would , in those circumstances, disable the use of “mscdex.exe” in windows by placing the “rem” command at the beginning of this command line. This tells windows to treat this line as a “remark” and ignore it.

However……so as to retain the use of these drivers in DOS mode (they are essential in DOS if CD-drive functionality is to be provided), a new file is created called “dosstart.bat” and an exact copy of the REM’d line is placed in it and this file is read during the “restart in MS-DOS mode” . By this neat little trick , “protected mode” drivers are operational in windows and “real mode” drivers are used in MS-DOS mode.

This fact is used at the “command prompt only” to activate the line in “dosstart.bat” to supplement “config.sys” and “autoexec.bat” and thus load the CD-drive driver pair. Windows safe mode can then be loaded ( if desired ) using the “win /d:m” command at the “c:\windows>” prompt. So you can pick whether to use CD-drive access from the one or the other. NEAT !

An even neater trick is to copy the windows installation files from the CD onto a separate partition [or better still a separate drive] and run the installation, not from the CD, but from the Hard-Drive using a DOS command.
Just navigate to the folder holding the setup file and type "setup" at the prompt and hit enter.

However:
You are seem to be implying that the command line in the Config.sys file which loads your CD-ROM driver is ok but:
the the command line in the Autoexec.bat file which loads its partner Mscdex.exe is wrong [you think].

Do you have the floppy disk supplied by the CD-ROM manufacturer which is used to install the driver? This not only copies the necessary driver files [like Mscdex.exe] onto your c: drive, but also makes the necessary changes to the Config.sys & Autoexec.bat files.
You would need to check afterwards that all was well [that you didn't have multiple, identical command lines loading multiple drivers].
No need to figure out the syntax!

[mjc]

Another method.....

Get a Win95 bootdisk with CD ROM support (one can be found here (http://www.bootdisk.com)), use it allong with your floppy to boot, fdsik and format your hard drive (make two partitions, one about the size of the Win95 CD...this one should be a logical partition and not a primary), then when done use the boot floppy to copy the system files onto the C: partition, from the a: prompt sys_c: (space instead of underscore), then copy the autoexec and config files from the bootdisk, along with the CD drivers....(make sure that the drive letter for the CD is at least E: better yet make it something like M).


A couple of things to do first is to make sure that the boot disk will work, and you can copy the needed files directly from it to the hard drive and try it out with your CD drive to make sure it works....rename the current autexec and config files to something like .old...that way you can restore them if the boot disk files won't work.

Then after all the needed files are copied to the hard drive power down and swap out for your CD, boot up and you should now have the CD support you desire...on the hard drive. Then copy the contents of at least the Win9x folder from the CD to the D: partition, when that copying is finshed swtich to d: and then cd to win9x, the run setup....from then on it you don't really need your CD any more...you may also want to transfer any driver files to d: before you start to install...(you have all your drivers, don't You???)

------------------
mjc
Links list:Computer Links (http://www.dreamwater.org/tech/mjc/index.htm)

Celts are the men that heaven made mad, For all their battles are merry and their songs are all sad.

[Sylvander]

Hello Kathye

Here's the specific information you requested.

Command Line Switches
The following is the command line for MSCDEX.EXE:

MSCDEX.EXE: /D:x /M:n /E /V /L:x /S /K

The following table defines the MSCDEX.EXE command-line switches:

Switch
-Definition

/D:<device name>
- Allows you to specify a name for the device driver. This name must be identical to the device name used in the CONFIG.SYS file.

/M:<n>
- Specifies the number of sector buffers used to cache the path table of a CD-ROM disk. Typically, each drive should have a minimum of four to five buffers. The larger this number is, the less your computer will have to read directly from the CD-ROM drive.

/E
- Tells MSCDEX.EXE to use expanded memory if your system is using expanded memory.

/V
- Displays information on memory usage when you boot your PC.

/L:<drive letter>
- Allows you to specify the letter you want to assign to the first CD-ROM drive.

/S
- Allows the CD-ROM to be shared on MS-NET based systems.

/K
- Tells MSCDEX.EXE to use any KANJI (Japanese) file structures, if present, rather than the default of alphanumeric file structures.

If you ever figure this out perhaps you could explain it here.
I for one would like to make sense of it.