Unable to Save ISO from USB Flash Drive - Error: An unsupported command was received.

[dyehya]

Checklist

• I have been made aware that if my problem can be summarized as "I've created or tried to create a media using Rufus, and ...", and I am not including a log, this issue will be summarily closed.
• I looked at https://github.com/pbatard/rufus/wiki/FAQ to see if my question has already been answered.
• I performed a search in the issue tracker for similar issues using keywords relevant to my problem, such as the error message I got from the log.
• I clicked the 'Log' button (🗒️) or pressed Ctrl-L in Rufus, or used DebugView, and copy/pasted the log into the section that says <FULL LOG> below.
• The log I am copying is the FULL log, starting with the line Rufus version: x.y.z - I have NOT removed any part of it.

Additionally (if applicable):

• I ran a bad blocks check, by clicking Show advanced format options then Check device for bad blocks, and confirmed that my USB is not defective.
• I also tried one or more of the following:
  • Using a different USB drive.
  • Plugging the USB into a different port.
  • Running Rufus on a different computer.
• If using an image, I clicked on the (✓) button to compute the MD5, SHA1 and SHA256 checksums, which are therefore present in the log I copied. I confirmed, by performing an internet search, that these values match the ones from the official image.

Issue description

1. Created a bootable flash drive with Lenovo USB Recovery Creator.
2. I open Rufus and want to save as .ISO (so I can use it for virtual emulation which is not supported by .vhd/.vhdx)
3. I make sure the D: selected.
4. I click the save icon.
5. I change the file type to ISO and set the desired filename.
6. I try to save it but it fails with Error: An unsupported command was received.
7. Note: I can create it successfully with .vhdx (however the VHDX file is 29GB (full flash drive size instead of the 12GB in use size, not sure if I should make a separate bug about that or if it is expected to be the full flash drive including the unused size since I did vhdx and not vhd).

Error Message Screenshot

Log

Rufus x64 v4.11.2285
Windows version: Windows 11 Pro x64 (Build 26200.7462)
Syslinux versions: 4.07/2013-07-25, 6.04/pre1
Grub versions: 0.4.6a, 2.12
System locale ID: 0x0409 (en-US)
Will use default UI locale 0x0409
SetLGP: Successfully set NoDriveTypeAutorun policy to 0x0000009E
Localization set to 'en-US'
Found USB 2.0 device 'General UDisk USB Device' (048D:1234)
1 device found
Could not get Disk Extents: [0x00000001] Incorrect function.
Disk type: Removable, Disk size: 32 GB, Sector size: 512 bytes
Cylinders: 3824, Tracks per cylinder: 255, Sectors per track: 63
Partition type: MBR, NB Partitions: 1
Disk ID: 0x7B060725
Drive has a Windows 7 Master Boot Record
Partition 1:
  Type: FAT32 LBA (0x0c)
  Detected File System: FAT32
  Size: 29.3 GB (31448891392 bytes)
  Start Sector: 2048, Boot: Yes
Found 5 additional UEFI revocation filters from remote SBAT
Found 4 active Secure Boot certificate entries from remote
Found 1 revoked Secure Boot certificate entries from remote

Save to image operation started
Running command: 'dism /Capture-Ffu /CaptureDrive:\\.\PhysicalDrive2 /ImageFile:"C:\Users\ITAdmin\Downloads\Lenovo ThinkCentre M80s Desktop Type 11CV Windows 10 Pro x64 Recovery.iso" /Name:"RECOVERY" /Description:"Created by Rufus (https://rufus.ie)"'

Deployment Image Servicing and Management tool
Version: 10.0.26100.5074
Capturing image

Error: 50

The request is not supported.

The DISM log file can be found at C:\Windows\Logs\DISM\dism.log
Failed to capture FFU image: [0x00000032] The request is not supported.

This is the separate DISM log:

2026-01-02 17:52:12, Info                  DISM   PID=67444 TID=51208 Scratch directory set to 'C:\Users\ITAdmin\AppData\Local\Temp\'. - CDISMManager::put_ScratchDir
2026-01-02 17:52:12, Info                  DISM   PID=67444 TID=51208 DismCore.dll version: 10.0.26100.7019 - CDISMManager::FinalConstruct
2026-01-02 17:52:12, Info                  DISM   Initialized Panther logging at C:\Windows\Logs\DISM\dism.log
2026-01-02 17:52:12, Info                  DISM   PID=67444 TID=51208 Successfully loaded the ImageSession at "C:\Windows\SYSTEM32\Dism" - CDISMManager::LoadLocalImageSession
2026-01-02 17:52:12, Info                  DISM   Initialized Panther logging at C:\Windows\Logs\DISM\dism.log
2026-01-02 17:52:12, Info                  DISM   DISM Provider Store: PID=67444 TID=51208 Found and Initialized the DISM Logger. - CDISMProviderStore::Internal_InitializeLogger
2026-01-02 17:52:12, Info                  DISM   Initialized Panther logging at C:\Windows\Logs\DISM\dism.log
2026-01-02 17:52:12, Info                  DISM   DISM Manager: PID=67444 TID=51208 Successfully created the local image session and provider store. - CDISMManager::CreateLocalImageSession
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: <----- Starting Dism.exe session ----->
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: Host machine information: OS Version=10.0.26200, Running architecture=amd64, Number of processors=16
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: Instance information: Parent process=C:\Program Files\Rufus\Rufus.exe, Parent process PID=2088
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: Dism.exe version: 10.0.26100.5074
2026-01-02 17:52:12, Info                  DISM   DISM.EXE: Executing command line: dism /Capture-Ffu /CaptureDrive:\\.\PhysicalDrive2 /ImageFile:"C:\Users\ITAdmin\Downloads\Lenovo ThinkCentre M80s Desktop Type 11CV Windows 10 Pro x64 Recovery.iso" /Name:"RECOVERY" /Description:"Created by Rufus (https://rufus.ie)"
2026-01-02 17:52:13, Info                  DISM   DISM FFU Provider: Drive path = \\.\PhysicalDrive2
2026-01-02 17:52:13, Info                  DISM   DISM FFU Provider:   Disk size = 31457280000 Bytes (29.30 Gb)
2026-01-02 17:52:13, Info                  DISM   DISM FFU Provider: Partition Style = MBR
2026-01-02 17:52:13, Info                  DISM   DISM FFU Provider: Partition Count = 4
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: CDiskReader::GetOsInformation#286 failed with 0x80070490.
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: CDiskReader::GetBlockAllocationBitmap#136 failed with 0x80070032.
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: FfuCaptureInternal#429 failed with 0x80070032.
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: FfuCaptureInternal#573 failed with 0x80070032.
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: FfuCaptureImage#155 failed with 0x80070032.
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: PID=67444 TID=51208 onecore\base\ntsetup\opktools\dism\providers\ffuprovider\dll\ffumanager.cpp:786 - CFfuManager::Capture(hr:0x80070032)
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: PID=67444 TID=51208 Failed to capture an FFU image from '\\.\PhysicalDrive2'. - CFfuManager::InternalCmdCapture(hr:0x80070032)
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: PID=67444 TID=51208 "Error executing command" - CFfuManager::InternalExecuteCmd(hr:0x80070032)
2026-01-02 17:52:13, Error                 DISM   DISM FFU Provider: PID=67444 TID=51208 onecore\base\ntsetup\opktools\dism\providers\ffuprovider\dll\ffumanager.cpp:225 - CFfuManager::ExecuteCmdLine(hr:0x80070032)
2026-01-02 17:52:13, Error                 DISM   DISM.EXE: FfuManager processed the command line but failed. HRESULT=80070032
2026-01-02 17:52:13, Info                  DISM   DISM.EXE: Image session has been closed. Reboot required=no.
2026-01-02 17:52:13, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:13, Info                  DISM   DISM.EXE: <----- Ending Dism.exe session ----->
2026-01-02 17:52:13, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:59, Info                  DISM   PID=7724 TID=29444 Scratch directory set to 'C:\Users\ITAdmin\AppData\Local\Temp\'. - CDISMManager::put_ScratchDir
2026-01-02 17:52:59, Info                  DISM   PID=7724 TID=29444 DismCore.dll version: 10.0.26100.7019 - CDISMManager::FinalConstruct
2026-01-02 17:52:59, Info                  DISM   Initialized Panther logging at C:\Windows\Logs\DISM\dism.log
2026-01-02 17:52:59, Info                  DISM   PID=7724 TID=29444 Successfully loaded the ImageSession at "C:\Windows\SYSTEM32\Dism" - CDISMManager::LoadLocalImageSession
2026-01-02 17:52:59, Info                  DISM   Initialized Panther logging at C:\Windows\Logs\DISM\dism.log
2026-01-02 17:52:59, Info                  DISM   DISM Provider Store: PID=7724 TID=29444 Found and Initialized the DISM Logger. - CDISMProviderStore::Internal_InitializeLogger
2026-01-02 17:52:59, Info                  DISM   Initialized Panther logging at C:\Windows\Logs\DISM\dism.log
2026-01-02 17:52:59, Info                  DISM   DISM Manager: PID=7724 TID=29444 Successfully created the local image session and provider store. - CDISMManager::CreateLocalImageSession
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: <----- Starting Dism.exe session ----->
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: Host machine information: OS Version=10.0.26200, Running architecture=amd64, Number of processors=16
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: Instance information: Parent process=C:\Program Files\Rufus\Rufus.exe, Parent process PID=57292
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: Dism.exe version: 10.0.26100.5074
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: Executing command line: dism /Capture-Ffu /CaptureDrive:\\.\PhysicalDrive2 /ImageFile:"C:\Users\ITAdmin\Downloads\Lenovo ThinkCentre M80s Desktop Type 11CV Windows 10 Pro x64 Recovery.iso" /Name:"RECOVERY" /Description:"Created by Rufus (https://rufus.ie)"
2026-01-02 17:52:59, Info                  DISM   DISM FFU Provider: Drive path = \\.\PhysicalDrive2
2026-01-02 17:52:59, Info                  DISM   DISM FFU Provider:   Disk size = 31457280000 Bytes (29.30 Gb)
2026-01-02 17:52:59, Info                  DISM   DISM FFU Provider: Partition Style = MBR
2026-01-02 17:52:59, Info                  DISM   DISM FFU Provider: Partition Count = 4
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: CDiskReader::GetOsInformation#286 failed with 0x80070490.
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: CDiskReader::GetBlockAllocationBitmap#136 failed with 0x80070032.
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: FfuCaptureInternal#429 failed with 0x80070032.
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: FfuCaptureInternal#573 failed with 0x80070032.
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: FfuCaptureImage#155 failed with 0x80070032.
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: PID=7724 TID=29444 onecore\base\ntsetup\opktools\dism\providers\ffuprovider\dll\ffumanager.cpp:786 - CFfuManager::Capture(hr:0x80070032)
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: PID=7724 TID=29444 Failed to capture an FFU image from '\\.\PhysicalDrive2'. - CFfuManager::InternalCmdCapture(hr:0x80070032)
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: PID=7724 TID=29444 "Error executing command" - CFfuManager::InternalExecuteCmd(hr:0x80070032)
2026-01-02 17:52:59, Error                 DISM   DISM FFU Provider: PID=7724 TID=29444 onecore\base\ntsetup\opktools\dism\providers\ffuprovider\dll\ffumanager.cpp:225 - CFfuManager::ExecuteCmdLine(hr:0x80070032)
2026-01-02 17:52:59, Error                 DISM   DISM.EXE: FfuManager processed the command line but failed. HRESULT=80070032
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: Image session has been closed. Reboot required=no.
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: 
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: <----- Ending Dism.exe session ----->
2026-01-02 17:52:59, Info                  DISM   DISM.EXE: 

[pbatard]

You are not trying to save to ISO. You are trying to save to FFU, which, because it is a Microsoft-specific implementation that is designed ONLY for Windows system drives is NOT generic and requires a very specific drive layout.

Therefore, if Microsoft's FFU generation reports that your source media is incompatible with saving to FFU, then it is incompatible with FFU, and you should revert to using ISO/VHD/VHDX.

There literally is nothing for me to do here. FFU is provided as a courtesy, in case it works and your drive layout is compatible. If it doesn't, you'll have to complain to Microsoft so that they make FFU compatible with non Windows system layouts.

[dyehya]

@pbatard, When I clicked the save icon, I selected iso. At no time did I try to save it as FFU. You can see it in the file name the FFU is trying to save as "ImageFile:"C:\Users\ITAdmin\Downloads\Lenovo ThinkCentre M80s Desktop Type 11CV Windows 10 Pro x64 Recovery.iso". So why is Rufus trying to use FFU to save an ISO?

I did successfully use VHDX but when I tried ISO again, it still tried FFU.

[pbatard]

Well, I did test the possibility that FFU could be picked when selecting ISO before I replied to you earlier, but I was not able to see any mismatch there.

I tried again with a path exactly the same as what you chose (I even created a C:\Users\ITAdmin\Downloads\ just for it), along with the Full Flash Image (*.ffu) type selected as filter, but can't get Rufus to not invoke the ISO creation command (oscdimg.exe) when the extension is .iso.

Here is what my log reports for that operation:

Save to image operation started
Running command: 'C:\Users\Pete\AppData\Local\Rufus\oscdimg.exe -g -h -k -l"d-live 13.2.0 gn amd64" -m -u2 -udfver102 F:\ C:\Users\ITAdmin\Downloads\Lenovo ThinkCentre M80s Desktop Type 11CV Windows 10 Pro x64 Recovery.iso'
Saved 'C:\Users\ITAdmin\Downloads\Lenovo ThinkCentre M80s Desktop Type 11CV Windows 10 Pro x64 Recovery.iso'

The content of the drive should have no incidence on the type selection process (but I am in the process of double checking), so I really don't get how you got the mismatch on your end. There has to be an environmental component to your issue. What happens if you try on a different computer?

[pbatard]

Aha! I can replicate the issue when a drive does not contain content that can be saved as FFU, and we therefore remove the filter from the list. It seems that when we do that, we ended up mapping ISO to FFU, which is why, when you have a drive that supports FFU, and you get the *.ffu option listed, saving to ISO works, but when *.ffu isn't listed as an option, FFU is selected as the option instead of ISO.

I'll fix that for the next release.

[pbatard]

This should be fixed in the latest builds now. You can try one such build by downloading the VS2022 artifacts from https://github.com/pbatard/rufus/actions/runs/21013879289.