Creating missing Windows 95 install floppy

Do you have a set of Windows 95 install floppies but one of them is missing/damaged? If they’re english, you can most probably download the images somewhere. But I haven’t found Czech anywhere.

The other option is to recreate it using Diamond Disk Layout Tool 1.00.0530 Рthe same that Microsoft used to build the original CABs (see LAYOUT.INF). Microsoft released the tools long time ago as MCABIN10.ZIP.

This is an example how I recreated missing disk 9 from Czech Windows 95 OEM (RTM – first release – version 4.00.950).

Rebuilding CAB files

Create a working directory, unzip MCABIN10.ZIP there, create SOURCE and OUT subdirectiories.

First, get the original files – e.g. from a CD of the same release and language version as your Windows 95 floppies. Some are available at WinWorld.

The files in CABs on the CD are in the same order as on the floppies (except there are some extra files at the end) – that’s great as the ddf can be rebuilt. Extract the CABs from the CD to the SOURCE subdirectory and save the file list (as it comes out of extract). You can use my WIN95.DDF file (for Czech Windows 95 RTM OEM) as a base to create your own using the file list you saved (note the .New Disk command which ends PRECOPY2.CAB to begin

Finally, run the process to create the CAB files in OUT subdirectory:

diamond /f win95.ddf


Rebuilding PRECOPY

If you need PRECOPY1.CAB or PRECOPY2.CAB, you need to rebuild them as MS probably did that too before releasing at least some versions of Windows 95 (PRECOPY2.CAB is not forward-linked to WIN95_02.CAB but WIN95_02.CAB is backward-linked to PRECOPY2.CAB). My PRECOPY.DDF.

diamond /f precopy.ddf


Finalizing the CAB files

Recreated WIN95_02.CAB is not identical to the original one (don’t know why) but other CABs are – with one exception – the setID¬†(two bytes at offset 20h) which is randomly generated. Use hex editor to edit the setID (two bytes at offset 20h) to match the original files. Finally, set the file modification time (using e.g. Volkov Commander).

Creating the floppy

  1. Use WinImage (8.1 if you’re doing this on Windows 9x/ME) to format a floppy in DMF 2048 (2048B cluster size) format.
  2. Copy the required CAB file there and label the floppy (in my case: label a: W95OEMCSD9).
  3. Use disk editor to edit the label date/time to match the file.
  4. Copy the boot sector from another floppy in the set. This makes the floppy read-only for Windows.
This entry was posted in Uncategorized. Bookmark the permalink.