Win95/Dos/CDron Drive

I have a new Pentium 2/300 with a CDRom drive. It works fine in Windows95 and in a Dos Box within Win95. How do I get the drive to be recognised if I boot up straight into Dos using F8/Command prompt only or reboot into Dos mode. All I get is Invalid Drive Specification. I have tried installing CDRom.sys in Config.sys and MSCDEX in Autoexec .bat, however although the drive is recognised as drive E inthe bootup scrolling info OI still get the same result when bootup is completed.
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Is the CDROM in fact drive E?  If you only have one hard disk it should be recognized as drive D.  We can tell DOS which drive letter to assign with the /L switch using mscdex.  Please post your equipment list.

Also, please post your config.sys, autoexec.bat, config.dos, and autoexec.dos, since these files are important for bootup problems.
Without further information it's difficult to answer you.

My answer is based on the assumption you are using the correct driver (from the disk supplied with your system)  

On the information you have given about it being set as E: but not available, I suggest that maybe you are missing


from your CONFIG.SYS file, to inform the system you have up to 3 non-detected drives.

The exact syntax of CONFIG.SYS should be:

   DEVICE=C:\[directory]\[CDROM driver].SYS /D:[name assignment]

and your AUTOEXEC.BAT should have a line

   MSCDEX/D:[name assignment]

Theoretically this is about as simple as it gets. If you still have problems, check that:

- Any additional switches on the DEVICE= line are correct.
  Some drives request additional parameters like which IDE
  channel the drive is connected to.

- MSCDEX.EXE and the driver are both referenced correctly.
  Even I've spelt it wrong, got the path wrong, etc.

- You don't need additional drivers/parameters, if your drive
  is SCSI or connected to a sound card (unlikely these days).

Apart from these suggestions I really can't see what else could
be wrong if it works within Windows.

If the settings don't work, try looking at the CDROM driver settings Windows 95 uses. Right click on My Computer, choose
Properties, Device Manager tab and double click on

  CDROM\[your CDROM]

If it says No driver has been loaded in the last tab then you're probably using standard CD settings.

Let me know if this has been of any use.


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Could you post here your autoexec.bat and config.sys after the CD-ROM installation.

When you get to a prompt in real DOS (F8/"command prompt only" at bootup) try the following command:

X:\mscdex.exe /d:(CD drivename)

Where X= the driveletter and path to mscdex.exe.
Don't type the parenthesis and do type (CD drivename) exactly as it appears in your config.sys device line.

Then see if you can access the CD.

Hope this helps....


arwoodAuthor Commented:
Dear All
Thanks for the advice. Will try it out over next weekend when I have some time and advise the results.

Ralph Marotta:- I have 2 hard drives C: and D: so the CDRom should be Drive E:

Alan Wood
arwoodAuthor Commented:
Dear All
I was so intrigued I took this afternoon off to investigate.

A. Rmarotta, Datn and MagigrafI have 2 hard drives, C: and D:, so the CDrom should be E:.  With regard to posting config.sys and autoexec.bat please read on.

B.Re Tstaddon. I carried out the following steps:-

1. Removed config.sys(c.s) and autoexec.bat(ae.bat) from root directory leaving only io.sys, msdos.sys and

2. Restarted Win95 in MSdos mode from shutdown menu. Bootup screen displayed:-

"Loadhigh c:\windows\command\mscdex.exe/s/d:mscd002/v/m:15
 Device driver not found mscd001
 No valid CD Rom device drives selected"

Checked for E: - Invalid drive specification.

Where on earth did the system get hold of that line, it was in my original win3.11 ae.bat but pointing to the Dos directory.

3. Entered "exit" to go to Win95. E: drive found in explorer and Dos box.

4. Shut down and power off completely then reboot into Dos using F8/6. This time no mention of the line regarding mscdex in para2 above. No E: in Dos.

5. Type win for Win95. E: present in Explorer and Dos box.

6. Repeated 2 to 5 above with same results.

7. Make 1 line c.s as per old Win3.11 c.s

8. Boot up from power off into Dos mode via F8/6. No E: recognised

10. Into Win95, E:recognised in Explorer and Dos box.

11. Restarted Win95 in Dos mode via shut down mene as in 2 above. Now the E: drive is recognised in Dos mode and in Win95 explorer and Dos box.

12. Repeated 11 above with same result.

13. Shut down and switch off. Reboot F8/6, this time no E: as in 8 above.

Comment - It appears that when shuting down to MSdos from the shut down menu the mscdex.exe has remained in memory and now the Cdrom driver sbcd.sys can work.?????

14. Make ! line AE.B:-
"c:\windows\command\mscdex.exe/s/v/d:mscd001/m m:15" as above".

15. No luck when booting F8/6. Investigation revealed that deleting m:15 allowed the system to boot and E: recognised in F8/6 and Win95.

16 Funilly enough when Shuting down and restarting in Dos mode from the shut down menu I get the message:-

"Loadhigh etc" as in para 2, (including the parameter m:15)"

"MSCDEX already started"

Everything still works in Dos and Win95.

17 Rechecked rebooting from power off and via shut down menu and all works.

Conclusion:- The original mscdex line is still present somewhere, but where. It is not in any file that I can see. This only leaves the registry file. It appears that this was the main reason for screwing up my previous attempts before posting this question. Can anyone expand on where it comes from or the difference in boot up proceedure under the differing conditions. I have looked in my 1156 page tome on Win95 and it is completely quiet on the subject. I remain fascinated as to the reason.

Hope this was not too long. I will leave the question open for a while before allocating the points to allow for replies.


Alan Wood
Arwood, here is an answer for you, although the question is not open and has been locked by Tstaddon's proposed answer, therefore please reject that answer and request the appropriate party to post an answer you are willing to accept.

As to your problem, there are two issues to be confronted based upon your original question, " How do I get the drive to be recognised if I boot up straight into Dos using F8/Command prompt only or reboot into Dos mode. All I get is Invalid Drive Specification. I have tried installing CDRom.sys in Config.sys and MSCDEX in Autoexec .bat, however although the drive is recognised as drive E inthe bootup scrolling info OI still get the same result when bootup is completed".

First, if your cd rom drive is Adapti qualified, which I suspect it might be, you won't be able to access the cd rom in F8/MSDOS mode unless you load real mode drivers for it. When you do that though, this will conflict with the protected mode drivers that windows loads.

Second, the reason your not seeing the cd rom with the changes that you are making, especially when you removed the config.sys and autoexec.bat , is because (my presumption here) you have your cd rom drive connected to the IDE port on your sound blaster sound card and not on your motherboard's IDE bus. "SBCD.SYS" is a sound blaster cd drive driver. To enable the cd rom drive on the SB IDE bus, you must first load real mode drivers for the sound blaster card and then load the cd rom drivers. Windows cannot see the drive unless the sound cards IDE chipset is active.

Best regards,
Is there a dosstart.bat file in the windows directory?  Also, is the port address for your CD supposed to be 220, as posted in your line 7 above?
I assumed your CDROM was not an SB one, so I acknowledge you may need another DEVICE= line to activate the CD channel on the sound card. Sorry- it's a long time since I came across a CD linked up that way.

When the GUI boots it activates any compatible installed 32 bit drivers and loads MSCDEX automatically, regardless of the real mode drivers.

I've heard of the real mode drivers conflicting with their 32 bit counterparts, as Dew Associates said, but I've personally never seen it. Nevertheless it won't do any harm to try it.

This is why if you close down to the DOS prompt MSCDEX is sometimes still resident ("MSCDEX already started").

If you had a working command setup for Windows 3.11 try looking in CONFIG.DOS and AUTOEXEC.DOS to see if these are the working files. If they are, just copy them to overwrite your current AUTOEXEC.BAT and CONFIG.SYS.

Overwrite AUTOEXEC.WIN and CONFIG.WIN with these files as well, if they exist.

PLEASE Post your AUTOEXEC.BAT and CONFIG.SYS files as they are so we can all look at them.
arwoodAuthor Commented:
Dear All

Slight confusion. I had the same problem on both my new machine and my old one so I elected to problem solve on the old one so as to ensure no problems with working machine. This is a 486DX2/66 with a Soundblaster CDrom connected to the sound card.
As I said yesterday it now all works fine in all modes so the problem was basically solved by reference to Tstaddon's 1st reply. This worked fine on both machines using the appropriate driver for the CD Rom concerned.



I have only shown the lines which concern the problem.

Now to specific answers:-

Tstaddon - In the old machine it is a SB CDrom conected to the soundcard. I dont appear to have any conflicts with the 32 bit drivers.

Dew_assocites/Dennis - You are correct in your diagnosis as per above

Rmarotta - You appear to have cracked the outstanding issue of where the strange "loadhigh/--/mscdex/-/etc" comes from.It was in the file dosstart.bat together with a mouse driver line which I didnt think neccessary to mention earlier. This must have been created when I installed Win95 over my old 3.11. I have removed it and the final piece of the jigsaw was completed and I have learned a little more.

Thanks to you all

I should like to allocate 100 points each to Rmarotta, dew_associates and tstaddon as these were the replies which most helped me. Do any of you know how I can do this. If I simply accept the last answer only one of you will get the points. I will therefore leave the question open until You can advise how.

Thanks again

Alan Wood
How about:

- allocate 100 points to me, repost the question, under a
  new title and accept an answer from Rmarotta for 100 points

- Repost the question, under a 3rd heading, and
  accept an answer from dew_associates for 100 points

I only put my name first as my answer is the locked one and I think you have to accept or reject it.

Good luck!
Arwood, you only need to accept this answer and then post a specific answer for myself and RMArotta. Thanks! your consideration is appreciated!
arwoodAuthor Commented:
I will post new questions for Dew_associates and Rmarotta each for 100 points today
Regards and thanks again

Alan Wood
I've just been credited with 300 points. I think that's wrong, could you confirm?
tstaddon, that comes from the site as part of the grading process!
arwoodAuthor Commented:
Attn Tstadon

I only accepted to pay you 100 points however I,m not going to cry over spilt milk if I made a mistake.
Thanks again
Alan Wood
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