DomainKeys Identified Mail
A technique for authenticating email, to ensure it has not been 'spoofed' (i.e. sent from a different domain than that listed in the 'sender' field). DKIM uses cryptographic methods and is stored in a TXT record.
Even if you outsource the handling of your email, you will need to configure a DKIM and SPF record on your domain. See also SPF.
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