Sending encrypted mail with Apple Mail

Apple Mail has a nice feature that allows you to digitally sign and encrypt your messages. This is extremely important if you are sending sensitive information via e-mail because messages are usually sent over an unencrypted channel. This means that there is the potential of your message being intercepted by a third-party. By encrypting your messages, it means that only the recipient of the message can read them.

The process of setting this up is fairly straightforward. First you need a Secure Email Signing Certificate (Digital ID). The good news is that you can get one for free:

Personal E-mail Certificates - secure e-mail communications

Once you’ve gone through the fairly lengthy registration process, you will be able to request a certificate.

Select the Mozilla Firefox option and go through the request process. Eventually your browser will download your certificate, and if you are using Safari, import it into Keychain Access.

When you now use Apple Mail, your outgoing messages will be signed by default. When you receive signed messages from other people, their public certificates will be automatically imported into Keychain Access allowing you to send them encypted messages. Just click the lock icon when you create a new mail! Bingo!

For more information:

Mac OS X 10.3: Mail - How to Use a Secure Email Signing Certificate (Digital ID)