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Q243896: Dual Boot Windows 98/Windows NT 4.0 with FAT16 or NTFS Volumes

Article: Q243896
Product(s): Microsoft Windows NT
Version(s): WINDOWS:; winnt:4.0
Operating System(s): 
Keyword(s): kbenv win98
Last Modified: 06-AUG-2002

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The information in this article applies to:

- Microsoft Windows 98 
- Microsoft Windows NT Server version 4.0 
- Microsoft Windows NT Workstation version 4.0 
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SUMMARY
=======

This article describes how to dual boot between Windows NT 4.0 using an NTFS
partition of any size, while allowing Windows 98 to reside on a large volume
using FAT32.

For Windows 98 to coexist with Windows NT 4.0 on a large NTFS partition, a small
FAT active partition must exist at the beginning of the drive. Currently, FAT16
using the 32-KB cluster size is the only common file system that both operating
systems can address from Power On Self-Test (POST). Therefore, making a FAT
drive C partition that is 2 GB in size or less, ensures the proper cluster size
is used.

If the active partition is NTFS or large FAT16 using the 64-KB cluster size,
Windows 98 does not boot because these file systems are not accessible to the
boot code that Windows 98 uses. Likewise, if the active partition is FAT32,
Windows NT does not boot.


MORE INFORMATION
================

You can use the following procedure to define the partitions you need using the
Fdisk tool. After you install Windows NT, you should avoid formatting logical
drives as NTFS within the extended partition. Although you can do this from Disk
Administrator, it is not supported because Fdisk cannot recognize NTFS logical
drives within an extended partition. You should note that if you make NTFS
logical drives, any future deletion of a FAT logical drive under Fdisk results
in the accidental deletion of the first NTFS logical drive instead. To prevent
the accidental deletion of a NTFS logical drive, you should create all logical
drives within Fdisk and delete them from Disk Administrator. You should then
format the RAW logical drives from within the operating system that you want to
have access to that logical drive.

To prevent cumbersome workarounds to recover boot sectors and to ensure the
successful installation of Windows NT 4.0 to an NTFS partition while still being
able to dual boot with Windows 98, use the following steps:

1. Install Windows NT 4.0 from the floppy disks or CD-ROM.

2. In Windows NT Setup, create a primary drive C partition that is at least 300
  MB in size. Select FAT as the file system and proceed with a minimal
  installation of Windows NT (this installation of Windows NT will not exist
  later).

  NOTE: 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 Service Pack 4 (SP4) or later after
  Setup is finished. This is because the updated Atapi.sys driver from SP4
  enables Windows NT to view large IDE drives correctly.

3. Restart the computer using the Windows 98 startup disk. Run Fdisk and click
  Yes when you receive a prompt about Large Disk Support.

4. Create an extended partition that is as large as you want. Be sure to leave
  room at the end of the disk for the Windows NT boot partition that you will
  create later from the temporary installation of Windows NT on drive C.

  NOTE: When you create the extended partition, you must subtract the amount of
  space you want for Windows NT from the total space available for the extended
  partition. If Windows NT will ultimately reside on an NTFS partition, you can
  make the primary partition as large as you want. If you want to install
  Windows NT on a FAT16 partition, the partition must not exceed 2,048 MB in
  size. Exceeding 2,048 MB for a Windows NT FAT volume forces the use of 64-KB
  clusters, which is unsupported when dual booting Windows NT with Windows 95
  and Windows 98 (and causes Windows 95/98 Setup to be unsuccessful). For this
  reason, you should use NTFS when volumes greater than 2 GB are needed for
  Windows NT.

5. Fdisk prompts you to create a logical drive. You should make the logical
  drive for the Windows 98 installation the full length of the extended
  partition. If you intend on making more than one logical drive, the first
  drive should be your Windows 98 installation partition.


6. After your logical drive is created, quit Fdisk.

7. Restart the computer using the Windows 98 Startup disk and select CD-ROM
  support.

8. Change to the CD-ROM drive where the Windows 98 CD-ROM is located and go to
  the Win98 folder. Type "format <driveletter>" (without the quotation
  marks) (where <driveletter> is the logical drive on which you want to
  install Windows 98.

9. When format finishes, reboot into Windows NT 4.0 and run Disk Administrator.

10. At the end of the disk behind the extended partition, right-click in the
  free space and click Create to make a primary partition. This partition is
  the permanent location of Windows NT 4.0. Click "Commit the Changes Now" and
  format the partition as appropriate.

11. Restart the computer using the Windows 98 Startup disk and select CD-ROM
  support.

12. Change to the CD-ROM drive where the Windows 98 CD-ROM is located and go to
  the Win98 folder. Type "format c: /s" (without the quotation marks).

  NOTE: This action formats over the current installation of Windows NT 4.0,
  and creates the Bootsect.dos and Boot.ini entries for Windows when Windows
  NT 4.0 is installed to the new primary partition in the next step.

13. Run Windows NT 4.0 Setup from the floppy disks or CD-ROM.

  NOTE: If you are installing Windows NT 4.0 to a large IDE drive and the
  partition on which you are installing Windows NT resides on or past the
  first 7.8 GB of the hard disk, you should obtain the Atapi.exe file and
  follow the steps outlined in the following Microsoft Knowledge Base article
  before you install Windows NT:

  Q197667 Installing Windows NT on a Large IDE Hard Disk

  You can download the Atapi.exe file from the following Microsoft Web site:

  ftp://ftp.microsoft.com/bussys/winnt/winnt-unsup-ed/fixes/nt40/atapi/atapi.exe

14. In the text-mode portion of Windows NT Setup you can see your partitions.
  Highlight the last partition and press ENTER to continue the installation.
  This is your production installation of Windows NT.

15. When you are prompted, click Leave Current File System Intact.

  NOTE: If the boot partition on which you are installing Windows NT 4.0 is
  beyond the reach of INT13 BIOS calls, the controller driver is copied to the
  root of the C drive and named Ntbootdd.sys. This means the ARC path in the
  Boot.ini file uses SCSI syntax to address the drive. Using SCSI syntax to
  address the drive at POST can cause a 20-30 second delay after the Boot.ini
  (where the screen is black).

16. Finish installing Windows NT 4.0. Restart the computer using the Windows 98
  Startup disk and select CD-ROM support.

17. Change to the CD-ROM drive where the Windows 98 CD-ROM is located. Go to the
  Win98 folder and type "setup" (without the quotation marks) from the same
  location.


18. During Setup, do not install to the C:\Windows folder. Click Other and
  install to <driveletter>:\Windows (where <driveletter> is the
  logical drive on which you want to install Windows 98).

After Windows 98 Setup is finished, both operating systems boot normally and the
Boot.ini file is updated to show Windows 98 as a valid choice.

REFERENCES
==========

For additional information about partition types and Windows NT Setup, click the
article numbers below to view the articles in the Microsoft Knowledge Base:

  Q224526 Windows NT 4.0 Supports Maximum of 7.8-GB System Partition

  Q197667 Installing Windows NT on a Large IDE Hard Disk

  Q119497 Boot Partition Created During Setup Limited to 4 Gigabytes

  Q127851 Problems Access FAT16 Drives Larger Than 2 GB

  Q151414 Windows 95 Partition Types Not Recognized by Windows NT

  Q179144 Cannot View NTFS Logical Drive After Using Fdisk

Additional query words: winnt NT4 win9x dual-boot how to fail fails

======================================================================
Keywords          : kbenv win98 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWin98search kbWin98
Version           : WINDOWS:; winnt:4.0
Issue type        : kbinfo

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