DKIM

Why it matters

DKIM lets a receiving server confirm that a message really came from your domain and was not tampered with along the way. That proof raises trust and supports inbox placement. Together with SPF and DMARC, it is part of the baseline that mailbox providers now expect from any legitimate sender, and skipping it drags down deliverability.

How it works in practice

DKIM attaches a signature to each message, created with a private key held by the sender. The matching public key sits in your DNS. The receiving server uses that public key to verify the signature, confirming the message is authentic and unchanged. A valid signature supports delivery; a missing or broken one is a negative signal.

Common mistakes

A common mistake is setting up DKIM once and never rotating the keys or fixing them after a provider change, so signatures silently break. Another is enabling it on one sending tool but not another. A third is treating DKIM as optional, when providers increasingly require it for good placement.

How hubsell approaches it

hubsell signs outbound with DKIM through authenticated infrastructure and helps you publish the right DNS records, so your messages carry the proof providers look for.