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Email infrastructure
DNS, MX, MTA-STS, BIMI, and the routes mail relies on.
23 guides
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All Email infrastructure guides
How do I fix SPF PermError: too many DNS lookups?SPF PermError: too many DNS lookups means your record needs more than 10 DNS queries. Here is how to count your lookups and get back under the limit.
SMTP vs IMAP vs POP3: what's the difference?SMTP vs IMAP vs POP3: SMTP sends email, while IMAP and POP3 retrieve it. IMAP syncs across devices; POP3 downloads and deletes. Here's when to use each.
What Is a DNS Changer? Speed, Privacy & SecurityHow switching DNS servers changes your speed, privacy, and security — when a DNS changer helps, when it hurts, and how to pick a resolver.
How does DNS poisoning work and how can teams defend against it?DNS poisoning feeds resolvers forged answers that redirect users to attacker sites. How cache poisoning works, real incidents, and layered defenses.
How does POP3 work and why should security teams care?How POP3 works step by step, why its download-and-delete model creates security gaps, and how MSPs can lock down or retire legacy mail clients.
How can DNS poisoning redirect traffic and what stops it?Understand DNS poisoning: how it redirects traffic, detection signs, and concrete defenses IT teams can deploy.
How Do Gmail’s New Blue Verified Checkmarks Impact BIMI Adoption?Email authentication protocols like SPF, DKIM, and DMARC have become standard practice for protecting brand reputation, but many organizations still…
How can I create a DMARC record in DNS with Palisade?Create a DMARC record in DNS with Palisade: what to publish, the exact TXT syntax, where it goes, how to verify it's live, and how to fix common errors.
How Can Retail Brands Use BIMI to Boost Email Open Rates?Brand Indicators for Message Identification (BIMI) lets a retailer display its logo next to the email in the inbox.
Why Is My BIMI SVG Format Causing Logo Issues?Have you spent hours setting up your BIMI record only to find your logo is nowhere to be found in people’s inboxes?
What is an AAAA DNS record (Quad‑A explained)?What an AAAA (Quad‑A) DNS record is, how it maps a domain to an IPv6 address, how it differs from an A record, and how to add and test one correctly.
What is POP3? Post Office Protocol 3 ExplainedLearn how POP3 downloads emails for offline use and local storage.
What is IMAP? Internet Message Access Protocol BasicsLearn how IMAP syncs emails across devices with server-based access.
What is an A record? DNS Address Records ExplainedDiscover what A records are, how they function, and their role in web and email.
What is a CNAME record? DNS Alias Records ExplainedWhat a CNAME record is, how DNS aliases resolve to a canonical name, the rules that trip people up (no apex, no siblings), and how CNAMEs power email setup.
What is a TXT record? DNS Text Records ExplainedWhat a DNS TXT record is, how it works, the 255-character string limit, and how SPF, DKIM, DMARC, and BIMI all rely on it.
What is an Email Header?What an email header is, how to read the Received and Authentication-Results lines, why the From address can lie, and how headers expose spoofing.
What is a PTR Record? Reverse DNS Lookups ExplainedA PTR record maps an IP address back to a hostname for reverse DNS. Learn how PTR records work, why email servers require them, and how to set one up.
What is MTA-STS? SMTP Security Policy ExplainedWhat MTA-STS is, how it forces TLS on inbound SMTP, the DNS record and policy you publish, and how it pairs with SPF, DKIM, and DMARC to secure email.
What is a VMC? Verified Mark Certificates for BIMILearn about VMCs, digital certificates that verify logo ownership for BIMI. Discover how they enhance email trust and branding with DMARC.
What is a DNS? Domain Name System Basics ExplainedDiscover DNS, the internet’s address book. Learn how it translates domain names to IP addresses, supports email, and enhances security with SPF and DMARC.
What is an MX Record? Mail Exchange DNS ExplainedWhat an MX record is, how mail servers use priority to route email, the exact records for Google Workspace and Microsoft 365, and how to check yours.
What is BIMI? Brand Indicators for Message IdentificationWhat BIMI is, how it displays your verified logo in the inbox, the DMARC and certificate (VMC or CMC) requirements, and which email clients actually support it.