Wednesday, 17 August 2016

Convenient way to run MS-DOS utilities directly from an NTFS E2B drive

If you have several different DOS utilities (to flash a BIOS perhaps or run a DOS-based diagnostic) which are provided as .exe or .com files, then you may have trouble adding it to an NTFS E2B USB drive.

Usually, you would have to make a DOS-bootable floppy disk image or perhaps make a bootable USB flash drive and then 'capture' the flash drive as a FAT32 .imgPTN file using the MPI Tool Kit (MakePartImage). Actually, E2B will try to boot to IO.sys or Kernel.sys, so you do not have to 'SYS' the floppy image, just ensure that the correct boot files are present inside the image file.

Today, I found some DOS floppy disk images which contained NTFS drivers on a Russian site ( seems to not provide free downloads any more). This means that all you have to do, is copy your DOS utilities to a new folder on your NTFS E2B USB drive, boot to the floppy disk image and then run the DOS utility straight from the NTFS E2B drive.

Note: The FreeDOS floppy image included with E2B v1.83+ now includes a DOS NTFS driver, so you can access an NTFS E2B USB drive as drive C:. Because FreeDOS is used and not MS-DOS 8.0 however, long filenames are not displayed correctly and so it is not quite as good as the DOS4NTFS.IMZ image.

  1. Download one of the floppy images from the DOS4NTFS page (see summary below)
  2. The. IMZ format is not supported by grub4dos, so if the file ends with .IMZ, you must load the .IMZ file into WinImage and save it again as an .IMA file. E2B supports .IMA and .IMG formats.
  3. Copy the file to the \_ISO\DOS folder on your E2B USB drive
  4. Create a new folder on your E2B USB drive and copy your DOS flash utilities (or whatever) into it.
    For instance, the WD DOS-based diagnostic dlgdiag v5.25 can be added to a \dlgdiag525 folder.
  5. Boot to the floppy image file, press ENTER if prompted and then press ESC or F10 to get to the command prompt
  6. Now run your DOS utility, e.g. typeC:\dlgdiag525\dosdlg.exe

A: will be the floppy drive (image file). C: will be the E2B drive. Some boot images have V: as a ram-drive.

Images available

DOS4NTFS.IMZ - DOS 8 - long-filename supported. V: is ram-drive  (NTFS rd/wr)
FAR.img - PC-DOS v7.1 - long-filenames not displayed (NTFS rd/wr)
NC4NTFS.img - DOS 8 + NDOS - long-filenames not displayed, TAB auto-complete, V: is ram-drive (NTFS rd/wr)

Note: You should own a Windows OS licence in order to legally use MS-DOS!

Tip: If you want to permanently alter the files inside the floppy disk image, use a file extension of .imanomem. You can boot to the disk image and use DOS 'edit' or 'ncedit' to edit text files or copy/rename files using the DOS shell, etc. as you wish and the changes will remain after reboot.

For instance, I copied to the DOS4NTFS image (by copying it from the NC4NTFS image to the E2B drive and then back to the DOS4NTFS image) and then added a line to \AUTOEXEC.BAT to run ndos on boot so that I had command line tab autocompletion. As the image was full, I deleted one of the files that I felt I would not use (AUTOCHK.exe).

cd c:\mydos

Of course, you can also edit the image file using a utility such as WinImage.