How to Back Up the Entire Hard Drive of a Mac to an External Drive & Delete Duplicate Files

Time Machine for Mac OS X 10.5 and later works with any external hard drive.

With the release of Mac OS X 10.5, known as Leopard, Apple introduced a feature called "Time Machine." Time Machine is a full backup solution that provides insurance in case your primary hard drive fails or becomes corrupted. When you set up Time Machine with an external hard drive for the first time, the tool makes a complete backup of your entire hard drive and then does incremental backups while deleting duplicate files.

Things You'll Need

• Mac running OS X 10.5 or later
• External hard drive

Instructions

1. Turn on your external hard drive and connect it to your Mac computer using the USB or Firewire cable that came with it.

2. Click on the "System Preferences" icon in the dock.

3. Go to the "Time Machine" control panel underneath the "System" heading.

4. Click on the "Select Backup Disk" button.

5. Highlight the name of the external hard drive connected to your computer and click "Use for Backup."

6. Move the slider bar on the left side of the window from the "Off" position to the "On" position. This will enable Time Machine and begin the full backup of your entire hard drive. Time Machine will complete incremental backups every hour and, when necessary, delete duplicate files to use as little space as possible.

References

• Apple Support: Mac 101: Time Machine