You are using MSCDEX wrong. After /D: comes the name you gave the device, not the name of the driver file. So try removing ".SYS".

The same goes for VIDECD.SYS.
After /D: give the device a unique name.
You'll see that the original startup file assigned a name of "banana", but you can call it whatever you wish.
Just remember that both files must have the same device name.

I can’t get it to work.
What syntax should I put in these config files ?
The problem appears to be with autoexec.bat driver and letter assignment.

Normally, you have a line in config.sys

DEVICE=IDECD.SYS /D:MYCD001

and a corresponding one in autoexec.bat:

MSCDEX.EXE /D:MYCD001

There are additional parameters for MSCDEX that you might consider using, but they are not needed for it to work.

One thing that's important: the device name may clash with reserved names. Never use the name of the driver nor just the word "CDROM" (clashes with the old High Sierra standard, causing some pre-1990 CD-ROM games not to work).

YES !
Thanks , that worked.

Great!