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Encrypt that file for safety
by Gene Arnold
Operating systems: Mac OS 9.X/Mac OS X
One of the most overlooked features of Mac OS9 is its ability to protect a file with 56-bit encryption directly from the desktop. That way, only those knowing the password are able to open the file. As an added benefit, encrypting also compresses the file, making it perfect for email.
To encrypt a file, simply select the item in the Finder and choose File &endash; Encrypt. Then enter a password in the Apple File Security dialog box that appears, as shown in Figure A.
Now to complete the encryption all you need to do is click the Encrypt button. When you do, the utility begins encrypting the file. Once the encryption is complete, the file's icon will include a small key in the lower-left corner, as shown in Figure B.
While the encryption may not be the strongest in the workd, Apple estimates that it would take a super computer over 35 hours to possibly decode the document without the password. On the other hand, you can decode a file in a matter of seconds if you have the password.
To do so, simply double-click on the document. A dialog box appears requesting the password. Enter the password you used to encrypt the file and click the Decrypt button. (if you added the password to your key chain the file decrypts automatically.)
Due to the manner in which the Apple file Security encrypts data, you can't encrypt folders, disks, volumes, items in the System Folder or Trash Can, or files that are open or locked. In addition, you can't use the program to encrypt files that have already been encrypted.
