Install Leopard from a USB Drive using a restore DVD
So you want to install Leopard from a DMG file. I don’t know how you got it, and I don’t care. However you have a problem, you only have a USB drive.
You might have noticed that you can’t install Leopard by restoring a Leopard install DMG onto a USB drive, since most Macs wont boot from USB.
But if you have a Mac, odds are you have an old Apple Restore DVD lying around. If you have a Mac OS X Leopard restore DVDs that you got with your new mac, you might have noticed that those DVDs wont allow you to install onto an older mac…
In theory the information below should work with a Tiger DVD as well.
So you have a USB drive with a restored Leopard image on it, and you have a Leopard (or possibly Tiger) restore DVD from your new shiny mac.
Together they form a working Leopard install. I will enlighten you. The information below applies to a Leopard Restore DVD, so YMMV.
Boot the restore DVD by holding down C when restarting your computer with the DVD inserted. It will tell you that Leopard can’t be installed on this computer. Press OK, do NOT press Restart.
Open the Terminal application from the Utilities menu. By now your USB drive should be inserted and powered.
I am assuming some knowledge of using the command line.
Navigate to the Leopard partition on your USB drive:
cd "/Volumes/Mac OS X Install DVD/"
cd "System/Installation/CDIS/Mac OS X Installer.app/Contents/Mac OS/"
You have now entered the secret dungeon of the Mac OS X Installer.
This will run the installer:
./Mac OS X Installer ../../../../Packages/OSInstall.mpkg
Your Leopard install should now begin and you are on your way to Leopard Heaven.
