Thanks to: https://forums.hak5.org/index.php?/topic/15567-convert-bootable-usb-to-iso/. Download and install ImgBurn. It’s a free application, but be careful during installation that you don’t install the 3rd party crap with it. Make sure you select “Custom” during each screen and deselect the crapware that tries to sneak in.
Plug the bootable stick into your machine. Open the ImgBurn application. Now click on the “Create image file from files / folders”. Next to the Sources pane, click on the Browse Folder button.
Boot From the USB Drive
Select the folder or drive you want to convert. In this instance I’m just imaging the D: drive. Next, click on the Browse Folder button next to the Destination part. Select a location to store the .iso file, and the name for it.
In this instance I’m saving it to C:\Temp\New Folder and naming it Image.
Click the Advanced tab, and then the Bootable Disc tab. Check the Make Image Bootable checkbox, and click the Browse button next to Boot Image.
Browse to the Boot folder, and open the etfsboot.com file. Set the Developer ID to Microsoft Corporation and the Sectors To Load to 8.
Leave 07C0 in the Load Segment part. Now click the big Build button on the bottom-left.
How to Burn an ISO to USB With the Rufus Tool
Because we didn’t give the image a title, we get this error. Just click Yes to accept the default, or provide a name you desire. And you’ll receive a confirmation about what will happen next.
In my case, I actually had to go back to the advanced tab as well to permit making an image that exceeds the ISO standard size (Mine’s over 10GB).
And then patiently wait…. Enjoy your newly created .iso file.
Download and open Rufus tool. Insert a USB drive and select a device. Select Disk or ISO image.
Locate and select ISO image to burn. Under Image option, choose Standard Windows installation.
Leave other options alone and choose Start. Wait for the status to say "Ready," then close Rufus and remove the USB drive.
So you have an ISO file that you want on a flash drive or some other USB storage device.
You also need to be able to boot from it. Sounds straightforward, right? Copy the file over and you're done! Unfortunately, it's not that simple.
This process also works to burn a Windows 11 ISO to USB. However, doing so via Microsoft's Windows 11 media creation tool is best.
Time Required: "Burning" an ISO image file to a USB device, like a flash drive, usually takes less than 20 minutes, but the total time depends a lot on the size of the ISO file.
Properly burning an ISO to USB is different than copying the file or burning it to a disc.
With ISO burning, you're not technically "burning" anything to a USB drive. Adding to the complexity is that you plan on booting from the USB drive once you're done getting the ISO image on there.
The 10 Best USB Flash Drives for Easy, Reliable File Transfer.
Download Rufus, a free tool that will correctly prepare the USB drive, automatically extract the contents of the ISO file you have, and properly copy the files contained within it to your USB device, including any files in the ISO needed to make it bootable.
Rufus is a portable program (doesn't install), works on Windows 11, 10, 8, and 7, and will "burn" an ISO image file to any type of USB storage device you happen to have. If you'd prefer to use a different ISO-to-USB tool, some other good ones include balenaEtcher, UNetbootin, ISO to USB, and Universal USB Installer.
Of course, if you do choose another program, you won't be able to follow the instructions we've written here because they pertain specifically to Rufus. Open the version of Rufus you downloaded. The program will start right away. As we mentioned earlier, Rufus is a portable program, meaning that it just runs as is.
Detailed instructions on 'burning' an ISO image to a USB flash drive
This is a big reason why we prefer this ISO-to-USB program over some of the other options out there. When it first opens, you're asked whether the program should occasionally check for updates. It's up to you whether you want to enable this, but it's best to do so if you plan to use it again in the future.
Insert the flash drive or other USB device into your computer that you want to "burn" the ISO file to, assuming it's not already plugged in. Burning an ISO image to a USB drive will erase everything on the drive!
Before continuing, check that the drive is empty or that you've backed up any files you want to keep.
From the Device drop-down at the top of Rufus, choose the USB storage device you want to burn the ISO file to. Rufus tells you the size of the USB device, as well as the drive letter and current free space on the drive.
Use this information to double-check that you're choosing the correct device, assuming you have more than one plugged in.
Don't worry about the free space that's indicated, since you'll be erasing the entire drive as part of this process. If no drive is listed, or you can't find the one you're expecting to see, there might be an issue with the USB device you're planning on using for the ISO image, or Windows is having some sort of problem seeing the drive.
Try another device and/or another USB port on your computer, or close and reopen Rufus. From the Boot selection drop-down, make sure Disk or ISO image (Please select) is chosen.
Locate and select the ISO image you want to burn to the flash drive, and then press Open to load it into Rufus.
ISO to USB
Wait while the software inspects the ISO file you chose. This might take several seconds or may go by so quickly that you don't even notice. If you get an Unsupported ISO message, the ISO you chose isn't supported for burning to USB by Rufus. In this case, try one of the other programs listed in Step 1 or check with the maker of the ISO image for more help getting their software to work from a USB drive. Under the Image optionarea, pick Standard Windows installationif you see this and if that's the case.