ESD-USB: Create a Bootable Windows USB from an ESD File

An esd-usb job means turning a Windows ESD install image into a bootable USB drive you can install Windows from. An ESD (Electronic Software Download) file is the highly compressed install image Microsoft delivers through Windows Update and the Media Creation Tool. It cannot be written to USB directly the way an ISO can, so the reliable path has three stages: export the ESD to a WIM image with DISM, build an ISO from it, then write that ISO to USB with Rufus. This guide walks through all three.

You will need a USB drive of at least 8 GB, the ESD file (usually named install.esd), a PC running Windows with administrator rights, and about 30 minutes. Back up anything on the USB drive first: every method here erases it completely.

ESD-USB, Current image: create bootable USB from ESD file with Rufus

ESD-USB: What You Need Before You Start

First, find your ESD file. It is often in the Windows Update download cache (the $Windows.~BT folder) or wherever the Media Creation Tool saved it. Copy it to a simple folder path with no spaces, for example C:\ESD, because the commands below are easier to type that way.

Second, install the Windows Assessment and Deployment Kit (ADK) for your Windows version, making sure to include the Deployment Tools. That gives you oscdimg.exe, the tool that builds the ISO. It is normally found under C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools\amd64\, though the exact folder varies with the ADK version.

Step 1: Check What Is Inside the ESD

An ESD can hold several Windows editions as separate indexes, and you need to know which index to export. Open Command Prompt as administrator and run:

dism /Get-WimInfo /WimFile:C:\ESD\install.esd

Note the index number of the edition you want (for example, Index 1 for Windows 11 Pro). If there is only one index, use 1.

Step 2: Export the ESD to a WIM File

DISM can read ESD files directly, so export the edition you want into the less compressed WIM format:

dism /Export-Image /SourceImageFile:C:\ESD\install.esd /SourceIndex:1 /DestinationImageFile:C:\ESD\install.wim /Compress:max /CheckIntegrity

Replace the SourceIndex with the number from Step 1. This takes several minutes depending on the size of the image and the speed of your PC. The export keeps the file structure intact and verifies it with CheckIntegrity, so a failed export tells you the ESD itself is damaged rather than silently producing a bad image.

Step 3: Build an ISO from the Exported Image

To build a bootable ISO, you need the standard Windows ISO file structure (the boot, efi, and sources folders). The simplest way to get it is to mount an official Windows ISO of the same version, copy all of its files to a folder such as C:\ISO_files, and replace its sources\install.wim (or install.esd) with the install.wim you exported in Step 2.

Then build the ISO with oscdimg from an administrator Command Prompt:

"C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools\amd64\oscdimg.exe" -m -o -u2 -udfver102 -bootdata:2#p0,e,bC:\ISO_files\boot\etfsboot.com#pEF,e,bC:\ISO_files\efi\microsoft\boot\efisys.bin C:\ISO_files C:\ESD\Windows.iso

Adjust the oscdimg path to your ADK install if it differs. Once it finishes, verify the ISO by mounting it in File Explorer (right-click > Mount) and checking that the sources folder contains your install.wim and the boot folders are present.

Step 4: Write the ISO to USB with Rufus

1. Download Rufus from its official site and run it (no install needed). Insert your USB drive.
2. In Rufus, confirm the correct USB drive is selected under Device. This matters if more than one USB disk is connected.
3. Under Boot selection, click Select and choose the Windows.iso you built in Step 3.
4. For Partition scheme, choose GPT for UEFI computers (almost every PC sold in recent years) or MBR for older BIOS systems. Choose FAT32 as the file system for the widest compatibility.
5. Click Start, then OK on the warning that all data on the drive will be destroyed. The write takes several minutes.
6. When Rufus reports Ready, close it. Your bootable USB is done: plug it into the target PC, boot from it (usually via the boot menu key or by changing the boot order in BIOS/UEFI), and install Windows normally.

If Rufus reports that the file system cannot be used with this type of ISO, switch the file system from FAT32 to NTFS and click Start again. This happens when the install image is larger than FAT32’s 4 GB single-file limit.

Frequently Asked Questions

Can Rufus write an ESD file directly to USB?
No. Rufus works from ISO images, not raw ESD files. That is why the ESD must first be exported with DISM and built into an ISO. Skipping that step is the most common reason ESD-to-USB attempts fail.

Where do I get a Windows ESD file?
ESD files come from Windows Update downloads (check the $Windows.~BT cache folder) or from the Media Creation Tool’s download process. If you only need install media and do not already have an ESD, downloading the official ISO directly is simpler than going through ESD at all.

Which index should I export if the ESD has several?
Run dism /Get-WimInfo first and export the index matching the edition you want to install. Exporting the wrong index gives you a working USB that installs the wrong edition, so this step is worth the minute it takes.

GPT or MBR: which partition scheme should I pick in Rufus?
Pick GPT for UEFI systems and MBR for legacy BIOS systems. When in doubt, check the target PC: if it boots with Secure Boot or its disk is GPT, use GPT. Rufus also auto-detects the right scheme for the ISO in most cases.

Sources:

Microsoft Learn — DISM Image Management Command-Line Options: https://learn.microsoft.com/en-us/windows-hardware/manufacture/desktop/dism-image-management-command-line-options-s14

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Axee Davies

Axee Davies is the founder of AxeeTech, publishing gaming guides, codes, and Windows how-tos since March 2013. A tech enthusiast for 13+ years — starting with smartphones and Android rooting — he now runs a site that puts out a new guide every day for Roblox players, traders, and Windows users. More about AxeeTech

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