USB stick manufacturers will rejoice with this news.  No longer will their flash memory be limited with the FAT32 file system, but rather an unlimited size of storage space.

Up to this point FAT file systems had a limitation of 4GB for a single file size and up to 32GBs for an entire volume.  But no more.  Microsoft has released a new exFAT file system.  This means our USB sticks will become supersized and no longer need to worry about dynamic file structures of NTFS.  With USB memory getting bigger each year, this is great news for mobile storage.

On January 27 2009, Microsoft released their new exFAT file system.  Or extended File Allocation Table [exFAT]. Here is some information off the Microsoft website:

The exFAT file system is the successor to FAT32 in the FAT family of file systems. The exFAT file system is a new file format system to address the growing demand and size of mobile storage like USB sticks, PDAs, and solid state hard drives. What’s nice about the exFAT file system

USB Tutorial: Turn a USB stick into a Hard Drive or Local Disk

NOTE: The original article can be found at the bottom of this page — jump there now.

UPDATE (2025): USB “Local Disk” without the XP-era driver hack

The old method on this page uses an XP-friendly INF/registry trick to flip the removable bit. It was clever, but on modern Windows 10/11 it’s brittle (driver signing, updates) and many tools/policies now check the device’s hardware class, not a label you force with a file edit.

What changed

• Windows storage stack + signing tightened; spoofed drivers are fragile after updates.
• Backup/imaging/installers increasingly verify true fixed disk at the controller level.
• Enterprise policies often block anything enumerating as “removable,” regardless of UI text.

What works now

Use hardware that natively enumerates as a fixed disk. The device tells Windows “I’m a hard drive,” so Disk Management, BitLocker, and picky installers behave accordingly—no per-PC driver editing.

Product we tested

Nexcopy USB HDD Fixed Disk appears as a Local Disk on any host (controller/firmware set). No utilities, no INF edits, just plug in. It’s suited for tools that require “Local Disk,” imaging, BitLocker, or multi-partition workflows.

Quick self-check

• Just need multiple partitions? Windows can create multiple partitions on many USB sticks. They won’t enumerate as “fixed,” but the partitions work—standard USB is fine.
• Need true “Local Disk” behavior? Choose fixed-disk hardware (e.g., Nexcopy) for installers that refuse “removable,” full-disk imaging, BitLocker parity, or corporate environments that block removable-class media.

Bottom line

The legacy hack is useful history, but for real-world deployments start with hardware that already identifies as a hard drive. For a full, modern walkthrough, see our new article covering 2025-ready options and workflows.

Original Article Starts Here

This is a very valuable tutorial, especially if you are looking to partition a USB stick.  Another application for turning a removable drive into a local disk, is that now many software programs can be loaded directly to a USB drive.  The first program which comes to mind is iTunes.  I know you need My Documents and a Local Disk to install it, so after this tutorial, I’ll try installing iTunes and share the results.

The process of turning a USB stick into a hard drive is fairly easy.  However, there are limitations.  For example, this works best with Windows XP operating systems.  You also need to update the drivers for the device for any computer you are going to use.  Typically, this isn’t a big deal as you can easily do this for your work and home computers.  However, this isn’t a great solution if you are trying to create a partitions USB stick for distribution to many possible users [say trade show give-away].

Couple of items you’ll need:

• USB_LocalDisk.zip files [download here]
• Windows XP
• USB stick

What we will do, is connected the USB stick, find the driver code, update the driver code and re-connect the device.  Simple.

Here are the details: