Now find the offset to properly mount the install partition in the resulting file. The resulting img file was only 137322496 in bytes and had an md5sum of 05b5788f10f7300c457e2aed735eb83a. Lastly, if you’re still having issues, a secondary USB or. Create a Mountain Lion bootable USB installation Open PowerISO and continue unregistered. It must be converted prior to mounting, and for this you will need dmg2img installed. Then, using Disk Utility within the Internet Recovery tools, partition and format the drive, then install a copy of OS X Mountain Lion. The internal dmg file (the one we really want) was 4333438336 bytes in size and had an md5sum of 68fd407bb74e4a2dd1913ce8bae80fc4. The unrolled dmg file I found was 4348218934 bytes in size and had an md5sum of 8b4869920cd740414fe6b7e3f0b1be3e. Inside was another file with the same name (although it is slightly smaller) which is the actual install image. If you try to dmg2img this file, you won’t get very far, so just extract it with 7-zip: You can now boot from any USB drive on your Lion-compatible Mac, just plug in the USB key, hold down the Option key during startup, and select the drive. The copy of OS X 10.8 (Mountain Lion) I downloaded was in the form of a file named “InstallESD.dmg”. Here are my ugly notes on creating a bootable OS X Mountain Lion (10.8)USB drive from/with Linux. I saw a few guides on how to make a bootable OS X flash drive, but not many on how to do it without already having access to an OS X machine.

You'll basically need to click four buttons: '10.8 Mountain Lion,' 'Use this copy,' 'Create a boot disk,' and, if you're using a. Found this from here, since it was useful I decided to paste it here. If you dont have a Mac that you can use to make a bootable USB for Lion, there are other sources to get a USB installer that is ready to use - such as. Just download the Lion Diskmaker app, unzip it, and run it.

Mountain lion os x bootable usb