Fdisk Does Not Recognize Full Size of Hard Disks Larger than 64 GB

The information in this article applies to:

• Microsoft Windows 98 Second Edition
• Microsoft Windows 98 Standard Edition

Symptoms

When you use Fdisk.exe to partition a hard disk that is larger than 64 GB (64 gigabytes, or 68,719,476,736 bytes) in size, Fdisk does not report the correct size of the hard disk.

The size that Fdisk reports is the full size of the hard disk minus 64 GB. For example, if the physical drive is 70.3 GB (75,484,122,112 bytes) in size, Fdisk reports the drive as being 6.3 GB (6,764,579,840 bytes) in size.

Cause

Fdisk uses some 16-bit values internally to calculate the size of the drive. Some of these variables overflow when the drive size is equal to or larger than 64 GB.

Resolution

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem.

NOTE: This hotfix is not designed for 48-bit logical block addressing (LBA) hard disks, and it is not supported on hard disks larger than 137 GB.

NOTE: The package that installs this fix contains both Windows 98 and Windows 98 Second Edition versions of the fix. The package automatically installs the correct version.

More Information

This package installs the updated Fdisk.exe to the Windows\Command and Windows\Options\Cabs folders, on a computer running Windows 98 or Windows 98 Second Edition. If you are starting a computer from a Windows 98 Startup Disk in order to partition and format the hard disk, you should copy the updated Fdisk.exe from the Windows\Command folder to the Startup Disk, replacing the original Windows 98 or Windows 98 Second Edition version of Fdisk.exe on the Startup Disk.

For additional information on issues with hard drives larger than 64GB, click the article number below to view the article in the Microsoft Knowledge Base:
 
    263045 Format Displays Size of Drives Larger Than 64 GB Incorrectly

There is no fix available for any version of Windows 95. For additional information, please see the following article in the Microsoft Knowledge Base:
 
    246818 Windows 95 Does Not Support Hard Disks Larger Than 32 GB

For additional information about Windows 98 and Windows 98 Second Edition hotfixes, click the article number below to view the article in the Microsoft Knowledge Base:
 
    206071 General Information About Windows 98 and Windows 98 Second Edition Hotfixes