Dual-booting all versions of Windows and Linux

   Dual-Boot    |    Win 8    |    Win 7    |    Vista    |    Win XP/2K/NT    |    Win9x/Me    |    How to    |    Legacy 9x Tweaks    |    SiteMap   


Here: Home > Dual-Boot > Dual-Boot Windows 9x/Me with other Operating Systems >

Dual-Boot or Multi-Boot:

Install Win NT (NTFS) on a Win9x system (FAT32)

Last reviewed: March 2004

How to dual-boot an NTFS Windows NT without data loss when a FAT32 Windows 9x is already installed on your PC. A dual-boot is created. No third-party boot manager is used here.

If you want to install NT on a Win 9x (FAT) system, go to Install Win NT (NTFS/FAT) on any Win9x (FAT).

Windows NT requires certain information to dual-boot with a Win9x. Windows NT can not create this information when the Win9x uses FAT32 and you want NT to use NTFS.

However, you can create the required information, present it to NT, and then NT can dual-boot with a FAT32 Win9x.

The FAT32 partition(s) will not be accessible to NT, and the NTFS partition(s) will not be accessible to Win9x.

[top of page]


Installing a Windows NT on a Windows 9x FAT32 system without losing data.

Already installed: Win9x using FAT32.
You want to add: Win NT using NTFS, without losing data, and dual-boot to either.
You are faced with two problems and both can be solved.

Problem 1:
The first problem is that, as you will see, you need two partitions. The way around this is to use a second hard disk, or create another partition with a utility like PartitionMagic ($), or BootIT ($), or Partition Manager (165KB, freeware) to repartition without loss of data.
PartitionMagic 5 was FREE with PC Magazine, June 2002 (PM is now ver. 8).
PartitionMagic 4 appears to be FREE at (not verified).
Click HERE to learn how to install another hard disk without changing current drive letters.
The alternative is to start fresh with Fdisk, and repartition, with total loss of data.

Problem 2:
A XP, 2K, NT dual-boots with a Win9x works (1) by creating Bootsect.dos (an image of the Win9x boot sector) and (2) by creating an extra line in c:\Boot.ini to call Bootsect.dos into use.

The second problem is that Windows NT can not create either of the above because NT does not recognize a FAT32 partition or the existence of a FAT32 Win9x. But, NT could use them if they existed! This problem can be overcome, though the method may seem a bit complex at first!

Note: When this dual-boot is established, it will be like having two computers, each with its own OS and hard disk space. NT will never 'see' the FAT32, and the FAT32 will never 'see' the NTFS.

[top of page]


Resolving the FAT32/NTFS incompatibility issue without losing data.

This aim is to create a correct Bootsect.dos in root of the PC system partition, and enable an option in NT's boot loader menu to boot to Win9x (FAT32).

Let's assume Win9x is installed on C: (FAT32), and NT will be installed using NTFS on what is now D: (a Logical partition or a second hard disk). We need to label them. Label C: as WinF32 and D: as WinNTFS.

A FAT32 Win9x is already installed on WinF32. Install Windows NT on WinNTFS formatting it to NTFS. It can not recognize the WinF32 partition. WinNTFS is now the PC system partition. Complete the NT installation. NT is now bootable. Win9x is not.

The Disk Administrator is used to change the Active partition from WinNTFS to WinF32. Win9x will boot for you, NT will not. The Win9x boot sector is now imaged to Bootsect.w98 (save to floppy).

Then the PC system partition is changed back to WinNTFS.
NT will now boot for you. Win9x will not boot - yet!
Finally Bootsect.w98 is copied from the floppy to the root of the WinNTFS partition (NT), and Boot.ini is edited to contain a line pointing to Bootsect.w98 - to the boot sector for WinF32.

Windows NT's boot loader will now work fine even though the Win9x is on a FAT32 partition. On reboot, the Boot Loader menu will have both Windows as legitimate boot options. Win9x will boot if selected, and will be using FAT32! And, Windows NT can also boot using NTFS!

NTFS will not 'see' the FAT32 partition (and visa versa) so be sure to label each drive.

[top of page]


Adding a NT (NTFS) on a Win9x FAT32 system:
This procedure presumes that C: is the PC system partition for the installed Win 9x.
If C: is not the PC system partition (unlikely), then you must not use,
and you must manually execute the Debug command (see below).

1. Hardware drivers compatible with next Windows (mainboard, hard disk, video, ..)
    For those in Windows, check list shown in \Drivers\ on its CD.
2. Win9x already installed on a partition that uses FAT32.
3. At least two partitions (either one must be large enough for its OS and data).
    All required data must be saved from the future Windows NT partition.
    All partitions should be labelled according to future use (FAT32 or NTFS).
4. All Hardware, & drivers, compatible with the Win9x should be fully installed.
5. Installation CD for the Win9x - it may be needed, sometime.
6. Installation CD for Win NT - obviously!
7. Backup of current Win9x boot files.
8. DOS5+/Win9x boot disk (CD access, and contains Sys, Fdisk, Format) - essential.
9. If C: is the Win9x PC system partition, then get THPC's (2KB, free)
    and unzip it to a DOS/Win9x floppy containing, Debug.exe,
    If C: is not the Win9x PC system partition, then read, below.
10. Floppies - for Win NT Setup disk set (3) & repair disk, ERD (1) - essential.
11. Make sure your system is suitable for running the new OS.

Win NT will control the boot up. A Reboot brings up its Boot Loader menu and you can select Win NT or Win9x as the next Windows to boot (if not, read Repair a Dual-boot).
Note: In an emergency any Win9x Startup Disk (with CD support) can be used for running a NT CD (boot up with it and run WINNT.EXE from the I386 folder of your NT CD).


How to install Windows NT using NTFS on a Win9x system that uses FAT32:
Make sure you have a second partition (Logical) or second hard disk (see above).
Make sure you have labelled each partition distinctively.
Remember: FAT32 can not see NTFS partitions. NTFS can not see FAT32 partitions.
 1. Prepare (above), and switch OFF anti-viral software (& check BIOS/CMOS also).
 2. Routinely backup the current boot files, and important data.
 3. Create a Win9x boot disk (CD support and contain Sys, Fdisk, Format) - vital.
 4. Unzipped to the Win9x partition or boot disk
    (Debug.exe & must be on floppy to run Bootsec).
 5. Install Win NT on the Logical partition or second hard disk.
      Let NT Format its own partition and use the NTFS file system.
      Make sure the correct target partition is selected (labelled WinNTFS).
      Create Win NT's ERD and boot disks (see above) - ESSENTIAL
 6. Reboot, and use NT's Disk Administrator to mark the Win9x partition as Active.
 7. Reboot (into Win9x).
 8. Run Bootsec.BAT from Win9x partition or floppy (remove write-protection).
 9. Reboot with boot disk and mark the NT partition as Active (WinNTFS).
10 Reboot (into NT).
11 Copy Bootsect.w98 from floppy to root of WinNTFS - the NT partition.
12 Edit Boot.ini in root of the WinNTFS partition (remove Read-only attribute)
      Add this line to the [operating systems] section of Boot.ini, and then Save it
      c:\bootsect.w98="Windows 9x" - include those quotes(" ").
13 Reboot. You can now dual-boot between Win9x (FAT32) and NT (NTFS).
14 Finally, always create a new Rescue Boot Disk when a new dual-boot is successful!
Note: Update NT with its SP 5(+) to use a large NTFS drive.
Note: If rebooting for hardware installation, be very sure you select the correct OS!

[top of page]


Specifying the Default OS to Boot, and the Boot Menu delay (the Timeout)

When you have established Dual-Booting, you will want to set which OS boots by default.

You can set the default OS (and the timeout) that you want via Control Panel.

1. Boot to the Win NT.

2. Go to Start > Control Panel > System > Advanced tab

3. Under Startup and Recovery, click Settings.

4. Under System startup, in the Default operating system list, click the OS that you want to start when you turn on, or restart, your computer.

5. Also select the Display list of operating systems for check box, and then type the number of seconds for which you want the list displayed before the default OS starts automatically.

You can also edit the boot options file (click Edit). Be careful of typing errors if modifying the boot options file (Boot.ini), because doing so may make your computer unusable.

[top of page]

BOOTSEC.ZIP contains Bootsec.bat and Bootread.scr which can run from your Win9x partition or your floppy (3.48 KB).

Bootsec.bat runs Bootread.scr which is a Debug routine that creates an image of the C: drive boot sector (FAT32) in Bootsect.w98 which is stored on a floppy. Bootsect.w98 is later copied to the root of the NT PC system partition (NTFS). will work for you if Win9x is installed on C:. Otherwise do not use it.

If Win9x is not installed on C: then you must run Debug manually as follows:

Boot into Win9x, open a DOS Prompt, and type the following:
L 100 2 0 1
N bootsect.w98

Press Enter after entering each line. This will create Bootsect.w98 on the root of your hard disk. Copy the Bootsect.w98 file to a DOS5+/Win9x floppy.

Important: The 2 in L 100 2 0 1 represents the C: partition. If C: is not the PC system partition for Win 9x, then change that 2 to 3 for D:, or to 4 for E:, or 5 for F:, ... Those numbers are in Hexadeciminal.

[top of page]


The system boot files for each Windows will be on its own PC system partition..

• When using NTFS for NT then the NT partition can be larger than 2GB (you need SP5 for greater than 7.8GB).

• You should try to install NT on a Primary partition, preferable on a different hard disk if you can.

• Win9x does not like more than one Primary partition per hard disk. However, Win9x can not 'see' the NTFS partition in a NT (NTFS) + Win9x dual-boot!

• You can download a free FAT32 utility from SysInternals to read data on your FAT32 partition. For a small charge, the full version lets you read from and write to FAT32 partitions.

• You must install SP5, or later, for NT4.0 if you intend to also install Windows XP or 2000. This update makes NT's NTFS compatible with the NTFS used by XP and 2000.

• From Microsoft: If you are installing Windows NT to an IDE drive that is larger than 7.8 GB, you need to install Windows NT 4.0 SP 4 (SP5), or later, immediately after Setup is finished. This enables NT to view large IDE drives correctly.

• From Microsoft: To prevent the accidental deletion of an NTFS logical drive, you should create all logical drives within Fdisk and delete them from Disk Administrator

• From Microsoft: After NT is installed, you should avoid formatting logical drives as NTFS within the extended partition.

[top of page]


Starting fresh:

It may be that you are starting fresh (clean hard disks).

If so, then you can still use the above technique,
use Microsoft's recommended method in Microsoft Knowledge Base Article - 243896
How to Dual Boot Windows 98 and Windows NT 4.0 with FAT32 or NTFS Volumes

Create Floppies.
To create NT's Setup Boot Disks (3) run winnt32 /o from the CD.
To create NT's Emergency Repair Disk (1), ERD, run rdisk.exe /s
To create Win9x's Startup Disk go to Control Panel > Add/Remove Programs > Startup Disk.

Note: If rebooting for hardware installation, be sure you select the correct OS!

[top of page]


NEVER dual-boot without your personal safety net - a BOOT DISK for XP/2K/NT.
If stuck, use a Win9x Startup Disk (CD support), and run WINNT.EXE from I386 folder on CD.

RESCUE BOOT DISK for when XP, 2K, NT will not boot - ESSENTIAL, 1 floppy
   Create a bootable floppy to get XP/2K/NT running even if the boot record,
   or boot files, are ever a problem. Write-protect and keep it safe.
      Format a floppy with that XP, 2K, or NT. It must be a full XP/2K/NT format.
      Alter file Attributes (Attrib -r -s -h) of these files in root of C: (PC system partition)
      Boot.ini, NTLDR,, and Bootsect.dos & Ntbootdd.sys (if present)
      (plus Arcldr.exe & Arcsetup.exe - for Windows 2K) and copy them to the floppy.
      Write-protect the floppy. Then restore original Attributes to the files on C:.
      Read the Rescue Boot Disk page for fuller details, plus a much improved Rescue disk.
Use the CD: If you have a Bootable installation CD you should check if your BIOS
   supports booting from it. This is hugely convenient, but still make the floppy.
ERD XP, 2K, NT: Emergency Repair Disk - repair key Registry entries and partition geometry
2K/NT Setup Boot Disks: (4 floppies for 2K, or 3 for NT)
   Use WINNT32 and MAKEBT32 from 2K/NT (\Boot disk folder on CD).
   Use WINNT and MAKEBOOT from a non-2K/NT system (such as Win9x).
XP Setup Boot Disks: (6 floppies)
   Read the Microsoft page How to obtain Windows XP Setup boot disks.
   It provides free downloads that create setup boot floppies for all versions of Windows XP.
   Each download is specific to each XP version (Home/Pro; original/SP1/SP2).
Win9x/Me Startup Disk:
   (95+) From a Windows: Control Panel > Add/Remove Programs > Startup Disk tab.
   (98+) From true MS-DOS: Go to the Command folder in Windows, and type Bootdisk.
   Windows 95 Startup Disks do not have CD support (add your CD-ROM driver).
   You can download free Win9x/Me boot disks from (IDE CDrom Drivers Included).

[top of page]

Please remember that you alone are responsible for the consequences of any changes you make to your computer hardware or software.

Copyright © LarryM 1998-2015