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Cfadisk Inf May 2026

Tools like WinToUSB or manual installations of Windows on external drives often function better when the drive is recognized as Fixed.

Open cfadisk.inf in Notepad or any text editor. You will see a section similar to this:

[Manufacturer]
%MfgName%=Cfadisk_Install,NTx86,NTamd64

[Cfadisk_Install.NTx86]
%DiskDevDesc%=Cfadisk_Install, IDE\DiskGeneric_CF_1.01____________________


[Cfadisk_Install.NTamd64]
%DiskDevDesc%=Cfadisk_Install, IDE\DiskGeneric_CF_1.01____________________

You must edit the line under [Cfadisk_Install.NTx86] and [Cfadisk_Install.NTamd64]. Cfadisk Inf

Replace the existing hardware ID (IDE\DiskGeneric_CF_1.01____________________) with your hardware ID from Step 1.

Example: If your ID is IDE\DiskSanDisk_SDCFH-004G____________________HDX100.0, change the line to:

%DiskDevDesc%=Cfadisk_Install, IDE\DiskSanDisk_SDCFH-004G____________________HDX100.0

Save the file. You may need to save a copy to your desktop if the INF is read-only.

The process involves "tricking" the Windows Hardware ID selection process. Tools like WinToUSB or manual installations of Windows

A typical custom INF file contains:

[Version]
Signature="$WINDOWS NT$"
Class=DiskDrive
ClassGuid=4D36E967-E325-11CE-BFC1-08002BE10318
Provider=%ProviderName%
DriverVer=09/04/2012,5.1.2600.0

[Manufacturer]
%MfgName%=DiskDrive,NTx86


[DiskDrive.NTx86]
%DeviceDesc%=cfadisk_install,IDE\DiskCF____________________________

Key Section – Hardware ID:

The original cfadisk.sys driver was designed for industrial CompactFlash (CF) cards used in IDE adapters. These CF cards were often used as solid-state drives (SSDs) in embedded systems. Because they were meant to be permanent storage, the driver treated them as fixed disks.

Technicians discovered that by modifying the INF file (the Setup Information file used to install drivers), they could force Windows to apply this "Fixed Disk" logic to generic USB mass storage devices.

Cfadisk.inf refers to a modified system driver configuration, specifically targeting the cfadisk.sys (CompactFlash Adapter Disk Driver) originally developed by Hitachi (now Western Digital). This modification is a widely utilized technical workaround in the IT and hobbyist communities. It allows the Windows operating system to treat removable storage devices (such as USB flash drives and SD cards) as fixed local disks.

By altering the way Windows identifies the device hardware type, this driver unlocks advanced disk management features—such as the ability to create multiple partitions on a USB stick—which are normally restricted by the operating system.

Common issues and their resolutions: