DomainKeys Identified Mail, or DKIM, is a system for confirming the authenticity of an email message by using an e-signature. When DKIM is enabled for a particular domain name, a public cryptographic key is published to the global Domain Name System and a private one is stored on the mail server. When a new message is sent, a signature is issued using the private key and when the email message is delivered, that signature is checked by the receiving server using the public key. Thus, the receiver can easily recognize if the email message is legitimate or if the sender’s address has been spoofed. A mismatch will occur if the content of the email has been altered on its way as well, so DKIM can also be used to make sure that the sent and the received emails are identical and that nothing has been added or removed. This authentication system will increase your email safety, as you can validate the authenticity of the important emails that you receive and your partners can do likewise with the emails that you send them. Depending on the particular email service provider’s policies, an email that fails to pass the test may be removed or may appear in the recipient’s inbox with a warning sign.