Do this before you install Lion but after you download it from the Mac App Store. The only way to do this is to use your computer’s restore disk to reinstall Snow Leopard or an earlier version of OS X. But the only way to do that is on a system that doesn’t already have Lion installed. Some other sites have posted that you can re-download the file. If you already upgraded to Lion the install image is deleted by default and it is already too late. In order to do this you will need the OS X Lion installation file. A clean install usually fixes these kinds of problems. This is a backup plan so you don’t have to take your computer to Apple to fix it if the hard drive or SSD drive won’t boot anymore. While the first two and last option are good reasons, the third is the most important.
In the case of the Flash Drive we will also show you how to put two partitions on one 8GB or larger flash drive so that you will also have all your Mac apps on the drive ready to install after you install the OS.
For now those are your only two options since Macs won’t boot from an SD card. We will show you how to create your own installation DVD or USB Flash Drive. A USB Flash drive version will become available in the future, but there is a way to get a clean install from a DVD or USB Flash Drive now with some effort.
Apple disregarded these concerns with the release of Mac OS X 10.7 Lion by only allowing the initial release in the Mac App Store for download. Install OS X Lion 10.7 just as you installed previous versions of OS X.Installing a new operating system over the old one can create problems with stability. Use this disk to boot any OS X 10.7 Lion compatible Mac. You never know when you’ll need to do a fresh install. Now just wait for your new OS X Lion install USB stick to finish. The process copies the InstallESD.dmg image to the USB stick, verifies it and completes. If you are prompted for your user ID and password, enter them and hit OK. Once it appears on the Finder desktop, move its icon to the Disk Utility window. In Disk Utility, click the InstallESD.dmg icon.Ĭlick on the Restore tab. Drop it into the left-most windowpane inside of Disk Utility. Move the ESDInstall.dmg file from your Finder desktop to Disk Utility, as shown below. Double-click to open it.ĭouble-click the Disk Utility icon to open it. Open the Applications folder in Finder and locate the Utilities folder. Doing so endangers the installation application. Switch to Finder and paste the file to your Desktop. Right-click the InstallESD.dmg file and hit Copy. If you backed up the installation file as instructed and don’t see it here, find the backup.Īpple, which is selling a $70 USB install disk of its own in August, destroys this file at the completion of most installations. Here you’ll find the InstallESD.dmg inside the ShareSupport folder. Inside the Contents folder you will find a SharedSupport folder. Right-click and select the option to Show Package Contents.ĭouble-click the Contents folder to open it. Use it to recover from if you make a mistake in this How to. This will create a copy of the installer labeled Install Mac OS X Lion Copy. Locate the installer in your Application folder and click it once to select it. Just leave the screen up or minimize it, and follow these instructions carefully. At the initial screen asking if you want to press Continue, DO NOT CLICK CONTINUE!ĭon’t hit Command either.
The install starts automatically - you need to stop it.
If you did already install it, then follow Apple’s Lion Recovery instructions to re-download OS X Lion again.Įither way, as soon as you install, get ready. Otherwise, you won’t be able to get the DMG file you need without having to download OS X Lion all over again. The optimum time to make your bootable disk is early in the install process.
You’ll also get some piece of mind in case of a system crash because you have a backup. Just create a Lion-bootable USB drive yourself and save your self $40. OS X 10.7 Lion is available on USB thumb drive but you’ve got to shell out about $70 for it.