Triple-Booting Windows 7, XP and DOS

Sometimes I need to do a little bit of retro-computing (not with virtual machines) to support some ancient hardware.

As far as compatibility is concerned, I have yet run across any weird piece of software that specifically requires Windows ME, 2000, Vista or Windows 8 to run that cannot be run with an OS one step up.

Windows 98 SE generally displaces anything from Windows 95 to Windows 98.

Windows 2000/XP usually run anything that are meant for NT starting from 4.0.

Windows NT 3.51 usually run Win32s programs that works on Win 3.1, except it’s way more stable.

Installation Order

The OSes should be installed from old to new:

  • DOS/Win 3.1 + 98 (SE)
  • XP
  • Windows 7

Reorganize boot menu

Windows XP installs a NT52 style (NTLDR) boot menu that recognizes DOS as a partition to boot. Windows 7 installer will install a NT60 style (BCD) boot menu that that the NTLDR loader as an OS (it’s called Earlier version of Windows) instead of directly booting to Windows XP. This means to get to Windows XP / DOS, you’ll have to select twice.

We can fix this by EasyBCD, which rebuilds the bootloader options for the installed OSes. Doing it with bcdedit is a major pain in the arse. There are some quirks to watch out for in the process no matter which path you choose:

  • You might need to boot into safe mode if the current BCD is locked.
  • Whatever OS that you are currently in calls itself C: and everybody else shifted according to the partition order.
  • When setting drive letter for the boot menu item, observe the drive letter scheme currently seen by the host OS. i.e. use C: when referring to the currently booted OS
  • Do not take up on EasyBCD’s offer to detect the drive letter automatically. They are likely to be wrong guesses that won’t boot, likely because of the shifting C: issue.

While you are at EasyBCD, it also offer the option of booting ISO (optical drives) and IMA (floppy) images, which I find it convenient for making the PC a tech service station.

Note that the DOS menu provided by EasyBCD went through an extra layer of indirection called GRUB4DOS, so it’s not as native as going through NT60 (BCD) > NT52 (NTLDR) > DOS in the sense that it installed foreign stuff not made by Microsoft such as Grub.

Tip about bcdedit

  • Some old versions of bcdedit’s /? menu did not tell you about the /store switch, which is necessary to manipulate foreign BCD files instead of the host BCD (that you used to boot to the current Windows you are working in).

 28 total views