Encryption

Windows XP Encryption
OS X Encryption

Windows XP Encryption

Windows XP Professional comes installed with the Encrypting File System (EFS) feature to encrypt stored files.

Note: You cannot encrypt files or folders on a volume that uses the FAT file system, nor gain access to encrypted files from Macintosh client computers.

Instructions

1. Click Start > All Programs > Accessories > Windows Explorer.
2. Locate the file that you want, right click the file, and then click Properties.
3. On the General tab, click Advanced.
4. Under Compress or Encrypt attributes, select the Encrypt contents to secure data check box, and then click OK.
5. Click OK. If the file is located in an unencrypted folder, you receive an Encryption Warning dialog box.

• To encrypt the file and the folder in which it is located, click Encrypt the file and the parent folder, and then click OK.
• To encrypt only the file, click Encrypt the file only, and then click OK.

External Links

Backing Up EFS Encryption Keys
Microsoft Encryption Guide
Removing Encryption

OSX Encryption

Macintosh OS X FileVault Encryption

The following article describes how to use the Macintosh OS X FileVault AES-128 encryption system.

Enabling FileVault Encryption

1. At the top left, click the Apple logo. In that menu, select System Preferences.

2. In the System Preferences window, click the Security icon; it looks like a safe in the shape of a house.

3. Click the button labeled Turn On FileVault, and enter your password. All files in your home directory (file:///Users/YourAccount) are now encrypted.

• Modifying files in your home directory now requires you to enter your password.
• To remove encryption, go back to the Security tab within System Preferences and click Turn Off FileVault.

OS X Encrypted Disk Image

What is an Encrypted Disk Image?

An encrypted disk image (.DMG) is a 128-bit encrypted file that, when opened, will prompt the user for a password. Once authenticated, the disk image will mount on the desktop allowing the user to copy data to the mounted disk image before unmounting the image to secure it.

Creating an Encrypted Disk Image

1. Launch the Disk Utility application. Go to Applications > Utilities > Disk Utility.

2. Go to File, then select New Blank Image. Enter a name for your image.

3. Select the size (this is permanent, and cannot be changed).

4. Under "Encryption", select "AES-128 Encryption" (or 256-bit in Leopard, 10.5).

5. Click OK and enter your password twice. Be sure to uncheck "Remember password in Keychain".

6. Your DMG will mount on your desktop, ready for files. To close it, control-click the icon and select "Eject".