To do a clean install, either boot the Windows NT install CD-Rom or setup
disks. When you get to the point, delete the existing NTFS and or other
partitions found. After you delete the partition(s) abort  the install, then
again restart the pc booting the CD-Rom or setup disks to avoid unexpected
drive letter assignments with your new install.

Depending on your drive's geometry Windows NT supports a system partition
(the first primary active partition and where the files required to start
the OS reside (boot sector)) limited to 7.8gB NTFS or 4gB Fat16, while the
boot partition (where the OS is installed) is not limited in size. You wont
be able to create a system partition greater than 4gB with Windows NT Setup;
if you need a system partition 4gB - 7.8 gB, you'll need to use Partition
Magic or use another NT machine to create the first primary active
partition. The system and boot partition can be the same partition.

If you created one large system/ boot partition > 7.8 gB and installed the
OS, it may work, but the problem is if you defragment the drive or service
pack the install and the files ntdetect.com, ntldr, boot.ini, and
ntbootdd.sys end up being relocated to a point beyond the 7.8 gB barrier,
then the bootstrap process wont be able to find them and the OS wont start.

Once the OS is installed you can use Disk Administrator to partition and
format the rest of your drive. You'll need atapi.sys from SP4 or later for
Windows NT to be able to recognize a drive larger than ~ 8 gB. See the first
article for the link and instructions.

Installing Windows NT on a Large IDE Hard Disk
http://support.microsoft.com/?id=197667

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

Windows NT 4.0 Supports Maximum of 7.8-GB System Partition
http://support.microsoft.com/?id=224526

Boot Partition Created During Setup Limited to 4 Gigabytes
http://support.microsoft.com/?id=119497

Windows NT Partitioning Rules During Setup
http://support.microsoft.com/?id=138364

Hi Tony,

it is possible that the intial stage of setup is incorrectly recognising your
hardware and selecting the wrong drivers to access it. Check the screen early in
setup where it identifies your hardware (ie: motherboard type etc..) and ensure
the right options are selected.

As to loading NT4 on a large harddisk, read this page:

http://nt4ref.zcm.com.au/bigdisk.htm

It should answer most of your questions regarding how to proceed, once you get
the install to run successfully.

Calvin.

Try the F6 loading atapi.sys from SP4 or later.

Hi Tony,

if you have access to the files - manually copy the latest ntldr. and
ntdetect.com (from Service Pack 6a) onto the affected machine's system partition
(overwriting the ones put there by the NT setup) and see if that helps :-)

Calvin.

Hi All,

At the end of the day, I went and bought Windows 2000 Pro. I loaded it,
partitioning my hard drive so that the C:drive was a 4MB FAT, and the D:
drive had the remaining 116 MB as NTFS. All installed nicely. Reinstalled
windows NT and hit the same problem. Installation seems to go OK, I supply
the ATAPI.dll from Service Pack 4 but when the system reboots to complete
the installation things get nasty. The system starts to load NT, then the
screen flickers and it goes into a reboot cycle.

In the end I gave up and installed Win 2000 Pro. I figure that some bit of
hardware in my brand spanking new computer is incompatible with NT. This is
not an ideal solution as I need to be able support clients using SQL Server
7.0 running under NT, but I can only have SQL Server 7.0 Desktop under Win
2000 Pro. I had to get the system back up and running so that I could get
back to work. I am keeping my fingers crossed that I can get by with my
current set up.

Anyway, thank you all so much for your help.

Regards
Tony