Create Windows 7/8 Bootable USB Drive on OS X

This note works for Windows (e.g. Windows 7, Windows 8, …), Linux … ISO image only, and all commands in Terminal.

If you’re interested in using Disk Utility, try this: Create OS X Mavericks Bootable USB Drive from AppStore Release, but DON’T forget to unmount partitions.

To launch a Terminal, simply open Spotlight and type Terminal, in most cases, you can see Terminal listed after ‘Ter‘.

For Windows 7/8 or later, Boot Camp Assistant is the BEST tool.
In ‘Select Tasks‘, CHECK ‘Create a Windows 7 or later version disk’ and UNCHECK all others.
In ‘Create Bootable USB Drive for Windows Installation‘, choose the right usb destination disk.

1 Prepare ISO Image

If you’re about to install on a Mac/Macbook, this conversion is necessary, but for pc/laptop, SKIP to 2 and use ISO.

Assume you have your windows 7 iso named as cn_windows_7_ultimate_with_sp1_x64_dvd_618537.iso
you may execute:

You see, a ‘.dmg’ is automatically appended to the file name.

2 Prepare USB Drive

Insert a USB Drive, 8GB or larger, USB 3.0 would be better.

Recognise Disk and Partition

On my MBP

The disk1 is the USB drive I’m burning the image to.

If you skip to Step 3 here, you’ll see Resource Busy.

Unmount Partitions

Find out what partition(s) is/are mounted

The mount point on my MBP is “/Volumes/UNTITLED 1”,


You can unmount by either device name or mount point

3 Burn Image

If you find dd dead slow, try a new block size, another choice is using rdisk instead of disk:

Create Windows 7/8 Bootable USB Drive on OS X by @sskaje: