DeliverabilityAn email preference center gives subscribers control over what they receive and how often — reducing spam complaints, keeping passive subscribers engaged, and directly improving deliverability metrics that matter to mailbox providers.
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DNS & DomainsDNS changes that affect email routing can cause mail to bounce or be delivered inconsistently if you're not careful. Learn the right sequence — TTL reduction, staged MX changes, and authentication record management — to cut over without downtime.
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DNS & DomainsPTR records and reverse DNS are among the most overlooked pieces of email infrastructure — yet a missing or misconfigured PTR record can cause your messages to be rejected before any content filter looks at them. Here's what PTR records are, why receiving servers check them, and how to get yours right.
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Email AuthenticationSPF records tell receiving servers which IPs are authorized to send email from your domain — but they're also one of the most commonly misconfigured DNS records. This guide covers how SPF works, how to set it up correctly, and how to avoid the lookup limit trap that quietly breaks many production setups.
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Email AuthenticationDKIM signs your outgoing emails with a cryptographic key so receiving servers can verify the message is genuine and hasn't been tampered with. This guide explains how DKIM signing works, how to set it up on managed and self-hosted infrastructure, and how to troubleshoot the issues that come up most often.
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Email AuthenticationDMARC is the policy layer that makes SPF and DKIM enforceable — it tells receiving servers what to do when someone tries to spoof your domain. This guide covers how DMARC works, how to set up your DMARC record safely in stages, and how to read the reports that show who is actually sending as your domain.
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Email SecurityBusiness email account compromise doesn't require exotic hacking techniques — most attacks succeed through phishing, reused passwords, and social engineering. This guide covers how attackers actually get into business email accounts, what they do once inside, and what defenses actually work.
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SMTP & InfrastructureTransactional email has fundamentally different infrastructure requirements from marketing campaigns — it needs to be fast, reliable, and completely isolated from anything that could drag down its deliverability. This guide covers the architecture decisions that matter: queue design, authentication, suppression lists, monitoring, and how to test before you go live.
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SMTP & InfrastructureA misconfigured SMTP server can be exploited as an open relay, used to send spam from your domain, or damage your sending reputation in ways that take weeks to repair. This practical hardening checklist covers open relay prevention, TLS enforcement, rate limiting, authentication requirements, and the ongoing monitoring that keeps your mail server secure long-term.
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