OK. Here are some instructions from Gizmodo that will put the ISO onto the flash drive with a Mac... they won't make it bootable though... read on...
Open a Terminal (under Utilities)
Run
diskutil listand determine the device node assigned to your flash media (e.g., /dev/disk2)Run
diskutil unmountDisk /dev/diskN(replace N with the disk number from the last command; in the previous example, N would be 2)Execute
sudo dd if=/path/to/downloaded.iso of=/dev/diskN bs=1m(replace /path/to/downloaded.iso with the path where the image file is located; for example, ./windows7.iso)Run
diskutil eject /dev/diskN, and remove your flash media when the command completes (this can take a few hours on slower drives)
Now... after you read all that, on the Gizmodo page it says that if you want to make it bootable you should use a utility called Live USB helper they link to (which isn't there any more) and use a Mac mounting tool (which isn't there either!) to force the ISO to mount on the Mac so you can copy the files over. So... that article may prove useful, but probably not. I can find other copies of Live USB helper out there, but they are all Windows executables.
One method that will work is to swap the hard drive out of the PC and into the Mac. Put your Windows 7 installation disc into the Mac optical drive, and install Windows 7 on that drive. Once it is up and running (don't worry about drivers yet), follow these steps.
- Run Command Prompt as administrator
- Type to Command Prompt:
%windir%\System32\Sysprep\Sysprep.exe, and hit Enter - In sysprep dialog that opens, choose “System Cleanup Action” as “Enter System Out-of-Box-Experience (OOBE)”, select “Generalize”, and select “Shutdown Options” as “Shutdown”. Click “OK”
- Sysprep generalizes now your Windows 7 setup and shuts down your computer. Do not run any other programs during this phase!
- Remove the drive from your Mac. Put it back into the PC.
- Boot the PC from sysprep generalized hard disk. You will notice Windows booting as if it was the first boot after installation, installing default and updating registry. One or two reboots are needed, depending on your system specifications
- When Windows finally boots up, you will need to enter all information as if this really was a new, fresh installation
All that is from here, but it applies in this situation a well, since you would be moving a Windows 7 installation from one computer to another. Considering that trying to make a Windows bootable USB stick with a Mac requires tools that either don't exist any more or are not being developed any more... this second method will most likely prove more dependable.
Answer from Bon Gart on Stack ExchangeTrying to make a bootable USB for Windows on a Mac? Here’s a simple way that worked for me in January 2024:
macos - How to create a bootable USB for Debian on Mac with Apple Silicon? - Unix & Linux Stack Exchange
How do I create a UEFI Windows Boot USB on a Mac?
Create UEFI boot USB on macOS Catalina
Hey, you! If you're looking for a place to have more personal, in-depth Mac discussions and perhaps want to venture off topic a bit more than you feel comfortable doing here, you should join our Discord server!
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
More on reddit.comHow to create a bootable USB on a Mac from DMG?
What format does a USB need to be bootable for Mac?
How do I make USB bootable from an ISO file on a Mac?
Videos
OK. Here are some instructions from Gizmodo that will put the ISO onto the flash drive with a Mac... they won't make it bootable though... read on...
Open a Terminal (under Utilities)
Run
diskutil listand determine the device node assigned to your flash media (e.g., /dev/disk2)Run
diskutil unmountDisk /dev/diskN(replace N with the disk number from the last command; in the previous example, N would be 2)Execute
sudo dd if=/path/to/downloaded.iso of=/dev/diskN bs=1m(replace /path/to/downloaded.iso with the path where the image file is located; for example, ./windows7.iso)Run
diskutil eject /dev/diskN, and remove your flash media when the command completes (this can take a few hours on slower drives)
Now... after you read all that, on the Gizmodo page it says that if you want to make it bootable you should use a utility called Live USB helper they link to (which isn't there any more) and use a Mac mounting tool (which isn't there either!) to force the ISO to mount on the Mac so you can copy the files over. So... that article may prove useful, but probably not. I can find other copies of Live USB helper out there, but they are all Windows executables.
One method that will work is to swap the hard drive out of the PC and into the Mac. Put your Windows 7 installation disc into the Mac optical drive, and install Windows 7 on that drive. Once it is up and running (don't worry about drivers yet), follow these steps.
- Run Command Prompt as administrator
- Type to Command Prompt:
%windir%\System32\Sysprep\Sysprep.exe, and hit Enter - In sysprep dialog that opens, choose “System Cleanup Action” as “Enter System Out-of-Box-Experience (OOBE)”, select “Generalize”, and select “Shutdown Options” as “Shutdown”. Click “OK”
- Sysprep generalizes now your Windows 7 setup and shuts down your computer. Do not run any other programs during this phase!
- Remove the drive from your Mac. Put it back into the PC.
- Boot the PC from sysprep generalized hard disk. You will notice Windows booting as if it was the first boot after installation, installing default and updating registry. One or two reboots are needed, depending on your system specifications
- When Windows finally boots up, you will need to enter all information as if this really was a new, fresh installation
All that is from here, but it applies in this situation a well, since you would be moving a Windows 7 installation from one computer to another. Considering that trying to make a Windows bootable USB stick with a Mac requires tools that either don't exist any more or are not being developed any more... this second method will most likely prove more dependable.
Assuming you have burnt your Windows CD into a ISO file with the tools like:
http://burn-osx.sourceforge.net/Pages/English/home.html
1. Jump into a folder here http://sourceforge.net/projects/unetbootin/files/UNetbootin/
2. Get the latest version of zip archive with the keyword "mac" in the filename.
3. Download and open it up on your Mac OS X desktop.
4. On Unetbootin interface, choose [Diskimage]->[ISO] and then select the Windows ISO file on your local hard drive.
5. Select the right USB Drive and then click [OK] to start writing ISO data onto your USB drive.
Once done, you're ready to boot your computer with this bootable USB drive, like a DVD installation disk.
I was searching for the best solution for hours, and then even ran into issues within the dated solutions that I saw here. I even tried creating a virtual machine, but my MacBook’s old 4 GB RAM couldn’t handle a Windows 10 VM (to be compatible with the flash drive).
I thought I’d share to save anyone else some trouble, at least for the time being. In my case, I was creating a bootable USB for Windows 11, and only had access to Macs and admin-blocked PCs.
Here are the steps that worked for me (no terminal required!):
Download the .iso file for the operating system of your choice from the Microsoft website.
Download UNetbootin at https://unetbootin.github.io. It’s safe and has been recommended here before, but as with any software on the internet, look it up yourself first just for the habit if anything.
Insert your USB flash drive.
Despite what you read elsewhere, you’ll want to reformat your USB from FAT32 to ExFAT. Search your Mac for “Disk Utility” and open it. Then select your flash drive and click “Erase” at the top. Enter a new name for the flash drive and use the dropdown to select “ExFAT”. Click OK.
Open the UNetbootin file and try to run it. If there is a security popup, click OK then go into your System Preferences -> Security and select “Open Anyway” next to UNetbootin.
Select the “Diskimage” radio button and search for the .iso file you downloaded in step 1. Also select the USB drive you are using. If concerned, you can find its name in the Disk Utility app, but mine was something like “Disk2s1”.
Click OK and wait. Could be several minutes loading certain files, so don’t worry - it’s still loading even if it’s not moving.
After it’s done, eject and use it to boot your new PC.
Hope this helps anyone else in my situation at least for a while.
tl;dr
$ sudo dd if=debian-12.8.0-amd64-netinst.iso of=/dev/disk4 bs=$(( 1024 * 1024 * 8))
You do not need any additional apps and you do not need to do any file conversions. Debian ISOs are built to be used directly by the dd command without modification (because the Debian release engineers are awesome like that!). And the dd command comes standard with all Macs since OS X has a BSD/BSD-like base to it.
Plug in the target USB drive.
Open up Disk Utility and find the USB drive on the left side. Right-click (command click) and select "Get Info". Do this for the TOP-MOST physical device. In my case, I am ignoring the "Lexar Flash" device. All the devices underneath that top-most device will be written over anyway.
Note the "BSD device node" assigned to this device. In my case
disk4.NOTE: This will translate to
/dev/disk4in the Terminal. If you seedisk6in the info panel, for example, then it will be/dev/disk6in the Terminal. Etc.Open up a Terminal window and type the following command (enter your user's password when prompted):
$ cd ~/Downloads $ sudo dd if=debian-12.8.0-amd64-netinst.iso of=/dev/disk4 bs=$(( 1024 * 1024 * 8))- NOTE: Change directory and file name of iso to match what you have. What I have here is just an example.
- NOTE(2): If you get a message from the system that it can't read the medium anymore, click "Eject".
- NOTE(3): If you do not include a
bs=...option, the same action will happen but it will take A LOT longer. So this is recommended on any modern system that can easily afford a large buffer to speed things up (any computer made past 1995 lol). - NOTE(4): The fancy
$(( 1024 * 1024 * 8))is using BASH's built-in calculator and I'm setting it to 8MB, essentially. The command requires the input in bytes, so we just do the quick math to give it a large value in bytes.
This process is not specific to Apple Silicon and should work the exact same way on Intel Macs.
I would suggest Etcher from Balena: https://etcher.balena.io/
It works on macOS(Intel & Apple Silicon), Linux and Windows. I downloaded the ISO and was able to successfully write it to a USB-C drive on my M1-based MacBook Pro using this software package.