Unlike the older versions of OS X that were distributed on optical media, the downloaded versions of OS X don’t provide a bootable installer. Instead, you run the installation app directly on your Mac under the older version of OS X. This works fine for the upgrade install and the non-startup drive install, but it doesn’t allow you to erase your startup drive, a necessary process if you want to perform a clean install.
What You Need for a Clean Install of OS X Mavericks
The OS X Mavericks Installer, available from the Mac App Store. A Mac that meets the minimum requirements for OS X Mavericks. A backup of your current startup drive. This can be a Time Machine backup or a clone of your startup drive. A startup drive that contains OS X Snow Leopard or later, and that you’re willing to erase.
Let’s Get Started
Once you complete these two preliminary tasks, you’re ready to begin the clean install process.
Boot From the OS X Mavericks Installer
- Plug the USB flash drive that contains the Mavericks installer into one of the USB ports on your Mac. I don’t recommend using an external USB hub for the installation. While it may work fine, sometimes you can run into an issue that will cause the install to fail. Why tempt fate? Use one of the USB ports on your Mac.
- Restart your Mac while holding down the option key
- The OS X startup manager will appear. Use your keyboard’s arrow keys to select the USB flash drive, which, if you haven’t changed the name, will be OS X Base System.
- Press the Enter key to start your Mac from the OS X Mavericks installer on the flash drive.
- After a short time, you’ll see the installer’s Welcome screen asking you to select a language. Make your selection and click the right-facing arrow button to continue.
Use Disk Utility to Erase the Startup Drive
- The Install OS X Mavericks window will display, along with the usual menu bar across the top of your monitor.
- From the menu bar select Utilities, Disk Utility.
- Disk Utility will launch and display the drives available to your Mac.
- In the Disk Utility sidebar, select your Mac’s startup drive, which is usually named Macintosh HD.
- Click the Erase tab.
- Make sure the Format drop-down menu is set to Mac OS Extended (Journaled).
- Click the Erase button.
- You will be asked to confirm that you really, really want to erase your startup drive. (You do have a current backup, right?) Click the Erase button to proceed.
- Your startup drive will be wiped clean, enabling you to perform a clean install of OS X Mavericks.
- Once the drive is erased, you can quit Disk Utility by selecting Disk Utility, Quit Disk Utility from the menu bar.
- You’ll be returned to the Mavericks installer.
Start the Mavericks Install Process
- In the Install OS X Mavericks screen, click the Continue button.
- The Mavericks licensing terms will display. Read through the terms, and then click Agree.
- The installer will display a list of drives attached to your Mac that you can install Mavericks on. Select the startup drive you erased in the previous step, and then click Install.
- The Mavericks installer will start the installation process, copying the new OS to your startup drive. The process can take a bit of time, anywhere from 15 minutes to an hour or more, depending on your Mac and how it’s configured. So relax, grab a coffee, or go for a walk. The Mavericks installer will continue to work at its own pace. When it’s ready, it will automatically restart your Mac.
- Once your Mac restarts, proceed to the next page to complete the OS X Mavericks initial configuration process.
Initial OS X Mavericks Setup
Because you’re performing a clean install of OS X Mavericks, you’ll need to run through the first-startup setup routine that configures some of the basic preferences needed by the OS, as well as create an administrator account to use with Mavericks. Have fun!
