DomainKeys Identified Mail, or DKIM, is a system for verifying the authenticity of an email using an electronic signature. When DKIM is enabled for a particular domain, a public key is published to the global DNS database and a private one is stored on the email server. When a new email is sent, a signature is issued using the private key and when the email is delivered, the signature is verified by the incoming POP3/IMAP mail server using the public key. Thus, the recipient can easily distinguish if the email message is authentic or if the sender’s address has been forged. A mismatch will appear if the content of the email has been modified in the meantime as well, so DKIM can also be used to ensure that the sent and the received email messages are identical and that nothing has been attached or removed. This email validation system will increase your email security, as you can verify the legitimacy of the important emails that you get and your associates can do the exact same thing with the email messages that you send them. Based on the particular email service provider’s adopted policy, an email that fails to pass the examination may be deleted or may appear in the receiver’s inbox with a warning flag.