Forum Discussion
Need help to burn dmg to usb for making Mac bootable USB drive
My wife's MacBook Air was stuck on system update after reboot and can't get into the desktop. Unfortunately, this is the only Apple device at our home. I need to make a bootable USB on my Windows 11 PC for reinstalling macOS on this Mac.
I heard it is possible to create a Mac bootable USB by burning dmg to USB in Windows PC. Can anyone confirm and how to do this on a Windows 11 or Windows 10 PC?
6 Replies
The most important step is to find the correct dmg file. After that, it is now a simple task to burn dmg file to USB in order to make it bootable for macOS install.
Quick guide: https://www.howgeekto.com/make-macos-bootable-usb-from-dmg
- 7-Zip can extract DMG files, but it doesn’t handle creating a bootable USB drive from them. This means you can get the contents out of the DMG, but making that USB drive bootable requires more steps and may not work seamlessly. So, you might end up with a USB that has files but isn’t actually bootable on a Mac.
- Is there a way to create a bootable USB drive using something other than tran/smac? I don't want to spend the $60 for this as I'm only going to use it once (and I waited too long, so the 15-day free trial ended....oops). I know Rufus doesn't work for this.<br><br>The Mac I'm trying to fix won't recognize the disk, so therefore I cannot reinstall the OS from the Mac itself. Any ideas?
- Once you get the Mac to burn dmg to usb, you might find yourself racing against the clock. You've got to download the macOS installer, which can take a while, especially if your internet connection is slow or if the App Store is busy. I've had situations where I had only a few hours and spent way too much of that time just waiting for downloads. Whenever you're using Terminal and dealing with commands like createinstallmedia, there's always a risk of screwing something up, especially if you accidentally select the wrong drive.
Enzozo You can use the built-in Command Prompt or Powershell utility to burn dmg to USB on Windows 10/11 along with the free 7-Zip app.
First, extract the content from macOS DMG file with the 7-Zip app. After that, insert your USB drive into the PC and format the drive with diskpart command:
select disk 1 clean create partition primary select partition 1 format fs=fat32 quick active assign letter=U exitNow, copy the extracted files to the USB drive:
xcopy C:\path\to\extracted\files\* U:\ /E /H /F
This process will burn the contents of the DMG file to the USB drive. Make sure to replace the placeholder paths and file names with the actual ones you are using.
Did all the diskpart commands up to Step 6 which fails - "The selected disk is not a fixed MBR disk.
The ACTIVE command can only be used on fixed MBR disks."
