DomainKeys Identified Mail, or DKIM, is a system for validating the legitimacy of an email message by using an e-signature. When DKIM is enabled for a certain domain name, a public encryption key is published to the global DNS system and a private one is kept on the mail server. If a new email is sent, a signature is issued using the private key and when the message is received, that signature is checked by the incoming mail server using the public key. Thus, the recipient can easily distinguish if the message is genuine or if the sender’s email address has been forged. A mismatch will appear if the content of the email has been changed on its way as well, so DKIM can also be used to make sure that the sent and the delivered email messages are identical and that nothing has been attached or deleted. This email validation system will enhance your email safety, as you can confirm the authenticity of the important email messages that you get and your associates can do the exact same thing with the emails that you send them. Depending on the particular mail service provider’s policies, an email that fails to pass the test may be deleted or may reach the receiver’s inbox with a warning.