DomainKeys Identified Mail, or DKIM, is a method for verifying the legitimacy of an email message using a digital signature. When DKIM is activated for a given domain, a public key is published to the global Domain Name System and a private one is stored on the mail server. If a new message is sent, a signature is generated using the private key and when the email message is delivered, the signature is checked by the incoming mail server using the public key. In this way, the receiver can easily recognize if the email is authentic or if the sender’s email address has been forged. A discrepancy will occur if the content of the email message has been modified on its way as well, so DKIM can also be used to ensure that the sent and the received emails are identical and that nothing has been added or removed. This email authentication system will strengthen your email security, since you can verify the legitimacy of the important emails that you receive and your associates can do likewise with the emails that you send them. Based on the particular email provider’s adopted policy, an email message that fails the check may be erased or may show up in the receiver’s inbox with a warning notification.