Using the Encrypting File System (Part I)

The Encrypted File System (EFS) is part of the Windows XP Professional OS, it allows users to easily encrypt/decrypt their data files. The way EFS works is Windows automatically creates the keys needed to encrypt and decrypt the files. Then when a file is requested by an application Windows uses the keys to decrypt the file, and when the file is saved it automatically re-encrypts it.

Use the steps below to enable file encryption:

• Open My Computer, and find the file or folder you want to encrypt.
• Right-click the file or folder, and select Properties.
• In General tab, press the Advanced button.
• Check the 'Encrypt contents to secure data' checkbox.
• Press OK buttons to dialog boxes.

Once you have selected the option, the contents of the file or folder will be encrypted. When encryption is setup at the folder level, all files are automatically encrypted when they're copied into the folder. To remove EFS encryption from a file or folder, all you have to do is follow the steps above and remove the check from the 'Encrypt contents to secure data' checkbox.

Note: You can not use both NTFS compression and encryption on the same file. If compression is enabled, it will automatically disable the encryption feature.