Create a bootable USB drive from a DMG file on Windows

A Mac machine needs to be reformatted with Lion. I backed up the Lion dmg file when I purchased it via the Mac App Store.

I now need to create a bootable USB drive from the DMG file but I need to be able to do it in Windows, preferring open source or at least free options.

How can I do this?

Use TransMac, which has a 15-day trial period and works flawlessly.

1. In the left pane, right click the USB Drive and select Format Disk for Mac

2. In the left pane, right click the USB Drive and select Restore with Disk Image

3. Point to your .dmg (or choose All Files to select an .iso) file and click Open.

It will take a few minutes depending on size of .dmg and speed of USB drive, but once done you can pop it into your mac, hold down the option key when turning on the mac and choose the USB drive.

TransMac worked for me, but first you need to partition your USB drive with GPT. It will not work if partitioned as MBR. diskpart on Windows can do this:

diskpart
DISKPART> list disk
(Find the disk number)
DISKPART> select disk 2
Disk 2 is now the selected disk.
DISKPART> clean
DiskPart succeeded in cleaning the disk.
DISKPART> convert gpt
DiskPart successfully converted the selected disk to GPT format.
DISKPART> create partition primary