DomainKeys Identified Mail, or DKIM, is a method for confirming the genuineness of an email message by using an electronic signature. When DKIM is enabled for a certain domain, a public encryption key is published to the global DNS system and a private one is stored on the mail server. If a new email message is sent, a signature is issued using the private key and when the email message is received, that signature is ‘scanned’ by the incoming POP3/IMAP email server using the public key. In this way, the receiver can easily know if the message is authentic or if the sender’s email address has been spoofed. A discrepancy will occur if the content of the email message has been altered in the meantime as well, so DomainKeys Identified Mail can also be used to ensure that the sent and the delivered email messages are identical and that nothing has been attached or removed. This email authentication system will boost your email safety, as you can validate the legitimacy of the important email messages that you get and your colleagues can do the same with the emails that you send them. Depending on the given mail service provider’s adopted policy, a message that fails to pass the check may be removed or may show up in the receiver’s mailbox with a warning symbol.