Wipe a Mac Clean
Planning on selling your old Mac? Is your system running slowly? Are you buried in files and programs and just want a fresh start? Wiping your Mac will erase all of your data and start with a fresh installation of your operating system. This can help your Mac run more smoothly, and is necessary if you want to protect your personal information when selling your computer. Follow this guide to wipe and restore any version of Mac OS X.
Steps
OS X 10.7 or Later
- Back up anything you want saved. Wiping will erase everything on the disk, including your operating system. Save any files you want to keep to an external hard drive, upload them to the cloud, or burn them to a DVD.
- Boot into the Recovery HD. Reboot the computer and hold down the Command + R keys while the computer boots. This will load the Recovery utility. Select the Recovery HD and press Continue.
- Open the Disk Utility. This program will allow you to manipulate your installed hard drives. You can access Disk Utility from the Recovery HD.
- Select your hard disk. In the left menu, you will see a list of your computer’s installed hard disks. Select the hard disk that you want to wipe.
- Click the Erase tab. Here you can select the format you want the disk to be. For OS X, the format should be Mac OS X Extended (Journaled). You can name the disk as well if you’d like.
- Click the Security Options button. By default, the drive will be reformatted with a one-pass method that writes zeros over the entire disk. This is moderately secure, but if you want more security, you can pick from several options.
- Click the Erase button. Your drive will now begin the wipe process. Depending on the Security Options you chose, this can take a significant amount of time. Once the process is complete, the drive will be wiped and formatted for your system.
- Reinstall OS X. You will need to Reinstall OS X Lion in order to use your Mac again. Click the Reinstall OS X option in the Recovery HD.
- You will need an internet connection in order to download the installation files. You may need to enter your Apple ID in to verify your account.
- Reinstall your iLife applications. Once your operating system has been installed, open the App Store. After entering your Apple ID and password, click the Purchases button. You can then download iPhoto, iMovie, and GarageBand.
OS X 10.6 or Earlier
- Back up anything you want saved. Wiping will erase everything on the disk, including your operating system. Save any files you want to keep to an external hard drive, upload them to the cloud, or burn them to a DVD.
- Boot up the installation DVD. Insert the installation DVD or CD into your computer and reboot. Press and hold the “C” button while the computer is rebooting to open the Installation menu.
- If you are using a USB drive with the installer on it, press and hold the Option key during startup and select the USB drive from the list of volumes.
- Open the Disk Utility. This program will allow you to manipulate your installed hard drives. You can access Disk Utility from the Utilities section of the Installation menu in OS X 10.6 or earlier.
- Click the Erase tab. Here you can select the format you want the disk to be. For OS X, the format should be Mac OS X Extended (Journaled). You can name the disk as well if you’d like.
- Click the Security Options button. By default, the drive will be reformatted with a one-pass method that writes zeros over the entire disk. This is moderately secure, but if you want more security, you can pick from several options.
- Click the Erase button. Your drive will now begin the wipe process. Depending on the Security Options you chose, this can take a significant amount of time. Once the process is complete, the drive will be wiped and formatted for your system.
- Once the Erase procedure is complete, click the Quit Disk Utility button.
- Start the reinstallation process. Click Continue when the Installer screen appears. You will also need to read and accept the license agreement.
- Select the hard drive. Make sure you select the hard drive you erased using Disk Utility. It should have a green arrow pointing to it.
- Click Install. A status bar will appear showing the progress of the operating system installation. Once the bar is full, click the Continue button, followed by the Restart button to complete the installation.
- If you are giving away or selling your computer, you are finished after this step. If you are keeping the computer to use yourself, continue on with the following steps.
- Configure your operating system. Once the computer reboots, you will be taken to a Welcome screen. Before you can use the operating system, you will need to select a few options.
- Select your country or region.
- Select your keyboard layout.
- Choose whether or not you want to Transfer-Files-from-PC-to-Mac from another computer.
- Connect to your wireless network (if available).
- Sign in with your Apple ID. Your Apple ID will be required to make purchases from the iTunes and App Stores. Creating an Apple ID is free if you don’t already have one.
- Create a user account. In order to use the Mac, you will need to create a user account. Pick a name and a password that you can easily remember, because you will need to enter it when installing new software or making any system changes.
- After creating an account, you can select a picture to associate with it.
- Install your extra software. Once the initial setup is complete, you will be taken to your desktop. Eject-a-CD-From-Your-Mac and then insert the Applications install disc that came with your Mac. If you have a MacBook Air, insert the Software Reinstall USB Drive.
- Install the bundled applications from the menu that appears. You will need to read and agree to the software license.
- When selecting a partition, make sure that it is highlighted with a green arrow.
- You can install all of the bundled software by clicking the Install button, or choose which ones you want by clicking the Customize button.
- You will need to enter the password you created in Step 12.
- Restart the computer once installation is complete.
Warnings
- When you wipe your Mac clean, your files, folders, user accounts, and network settings will be deleted. You may want to back up any files you want saved and review any custom settings you have in place before you begin the erasure procedure.
