How to Secure Files With Mac OS X Disk Utility

We all probably have sensitive information stored on our computers, readily available for anyone to see. To get a handle on information that can be dangerous in the wrong hands, Mac OS X's Disk Utilities allows you to create a Disk Image, fit to put on CD or store on your hard drive, that has 128-bit encryption. You'll need a password to read the Disk Image whether you read it from a CD-R or straight from your hard drive. Here is how to create a disk image.

Instructions

Difficulty: Moderate

Things You’ll Need:

• Apple Macintosh Computer running Mac OS X
• A CD-R if you want to store the image on disk

1. Launch Apple's Disk Utility. It's located in the Applications directory under Utilities.
2. Select "File" from the top menu of Apple's Disk Utility and select "New" > "New Blank Disk Image." You can also just click on the "New Image" icon on the toolbar or you can use the keyboard shortcut Alt-Command-N.
3. Type in a filename of the Disk Image you're creating in the "Save As" field. Make it as descriptive as you want.
4. Select "Where" you want to save the disk image on your computer. If you're planning on saving it on the hard drive, place the image where you will store it. Otherwise, place it on the desktop so you can find it easily.
5. Type in a "Volume Name" in the next text field. This is the name that will show up when your Disk Image has been mounted (if it's a CD, "mounted" means it's been inserted in your computer and is ready to be read).
6. Select "610MB (CD-ROM 74 min)" in the "Volume Size" drop-down box. This will make an image that'll fit perfectly on a CD-R. You can, however, make it whatever size you like--just make sure it's big enough to hold all the data you want to secure.
7. Select "128-bit AES encryption (recommended)" from the "Encryption" drop-down box.
8. Click "Create."
9. Type in a secure password--a combination of uppercase, lowercase letters, numbers and symbols--when Disk Utility prompts you to do so. Mac OS X Leopard shows you the strength of your password as you create it. Click "OK" when you're done and Disk Utility will create and mount the new image.
10. Copy over all the files you want to make private to your new Disk Image. It will be available in the "Devices" section of the Finder window.
11. Eject the Disk Image when you're done by clicking the eject button next to the newly created disk image icon or by dragging it to the Trash.
12. Move the Disk Image wherever you'd like. Just copy, move or burn the "diskimagename.dmg"--in this case "BankStuff.dmg"--to its final location. You will need to enter the password you specified earlier to read this disk image from now on.

Tips & Warnings

• Do not lose the password. You will not be able to reset it and all of your data will be trapped behind the password.