I can't create a NTFS partition over 4GB during installation.

A. During the text based portion of the NT installation, it is possible to create and format partitions. The maximum size for an NTFS partition is very large (16 exabytes), however the maximum size for a FAT partition under NT is 4GB (2GB under DOS). If you format a partition as NTFS during NT installation, it originally formats it as FAT and then converts it in the final stages of the NT installation, and this you are limited to a maximum partition size of 4GB during the NT installation.

Windows 2000 does not have this problem as it formats directly as NTFS and so does not hit the 4GB FAT limit.

To get round this problem there are several paths of action open to you

  1. Before starting the installation insert the disk into an existing NT installation and partition/format the disk using Disk Administrator and then insert the disk into the machine to be installed
  2. Partition the disk into smaller partitions, if you had a 5GB disk you could have a 1GB system partition, and a 4GB boot partition. The system partition is the partition NT's core startup files are located, boot.ini, ntldr and ntdetect.com (ntbootdd.sys if SCSI), and will normally be the active partition. The boot partition is the partition that NT stores the rest of its files, i.e. the %systemroot% directory
  3. Create a 4GB partition at installation time, and then extend the NTFS partition after installation has completed
    - Start Disk Administrator (Start - Programs - Administrative Tools - Disk Administrator)
    - Select the NTFS partition and holding down the Ctrl key select the unpartitioned space of the rest of the disk
    - From the Partition menu, select Extend Volume Set
    Note - You cannot extend a NTFS partition if it is the boot or system partition (as the boot/system partition cannot be part of a volume set)

If you are performing an unattended installation it is possible to create a greater than 4GB partition using the ExtendOEMPartition flag in the unattended file. This key causes text-mode setup to extend the partition on which the temporary Windows NT sources are located into any available unpartitioned space that physically follows it on the disk. Under the \[unattended\] section include the lines:

FileSystem = convertNTFS
ExtendOemPartition = 1, NoWait

The NoWait is only availble from Service Pack 1 and above.

Also if you are installing from a distribution kit you can copy the Service Pack 3 version of setupdd.sys and replace the version in i386 folder of the NT distribution set.

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For more information see knowledge base articles:

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