Spamhaus Sender Guidelines: The Deliverability Checklist Every Sender Needs
Use the Spamhaus Sender Guidelines to audit DNS, authentication, consent, bounces, and reputation before inbox placement becomes a crisis.
Oct 22, 202619 min read
Email Authentication
186 articles on email authentication.
Inbox Placement: What It Means, How to Measure It, and How to Improve It
Learn what inbox placement means, how it differs from delivery rate, how to calculate it, and practical ways to improve email performance.
Oct 21, 202623 min read
Phishing Emails: Definition, Deliverability Risks, and Prevention
Learn what phishing emails are, why they damage sender trust and deliverability, and how authentication, monitoring, and response reduce risk.
Oct 20, 202620 min read
Postmaster Email: Definition, Responsibilities, and Deliverability
Learn what a postmaster email is, why it matters for deliverability, and how to monitor bounces, complaints, authentication, and sender issues.
Oct 20, 202620 min read
Spam Complaints: Causes, Prevention, and Recovery for Senders
Learn what spam complaints mean, how they damage email deliverability, which metrics to track, and how to prevent and recover from them.
Oct 20, 202620 min read
Public Key Cryptography in Email: DKIM, TLS, and Trust
Learn how public key cryptography supports DKIM, TLS, DMARC alignment, secure key rotation, and stronger email deliverability.
Oct 20, 202623 min read
Quarantined Email: Meaning, Causes, and How to Prevent It
Learn what a quarantined email is, why security filters hold messages, how it affects deliverability, and how senders can prevent it.
Oct 20, 202624 min read
Return Path Email: What It Is and Why It Matters for Deliverability
Learn what a return path email address is, how it handles bounces, affects SPF and DMARC alignment, and supports stronger deliverability.
Oct 20, 202621 min read
Seed Test: What It Means for Email Deliverability
Learn what a seed test is, how inbox placement testing works, what results mean, and how to use seed tests to improve email deliverability.
Oct 20, 202622 min read
Sender ID Email Authentication: What It Is and Why It’s Legacy
Sender ID email authentication explained: how the legacy PRA check worked, why it matters less today, and how to move to SPF, DKIM, and DMARC.
Oct 20, 202622 min read
Sender Policy Framework (SPF): What It Is and How It Works
Learn how Sender Policy Framework (SPF) authorizes email senders, affects deliverability, and how to build, test, and maintain a valid SPF record.
Oct 19, 202623 min read
Sender Reputation: What It Means and How to Improve It
Learn what sender reputation means, which email signals affect it, why it changes deliverability, and practical steps to improve inbox placement.
Oct 19, 202621 min read
SMTP Configuration 421 Error: Diagnosis, Retries, and Deliverability Fixes
Solve an SMTP configuration 421 error with practical retry, DNS, authentication, connection, and sender-reputation troubleshooting steps.
Oct 19, 202620 min read
Reputation Monitoring for Transactional Email: A Practical Guide
Learn reputation monitoring for transactional email: track bounces, complaints, authentication, blocks, and inbox placement before deliverability suffers.
Oct 19, 202621 min read
SMTP Authentication: What It Is and How to Fix Errors
Learn how SMTP authentication verifies senders, prevents relay abuse, affects deliverability, and how to troubleshoot common SMTP AUTH errors.
Oct 19, 202623 min read
SMTP Relay: What It Is and How It Affects Email Delivery
Learn what an SMTP relay is, how it routes email, affects deliverability, and how to configure, secure, test, and troubleshoot it.
Oct 19, 202626 min read
Spam Folder: What It Means for Email Deliverability
Learn what the spam folder means in email deliverability, why messages land there, how spam placement is measured, and how senders improve inboxing.
Oct 19, 202621 min read
Reducing Unsubscribe Rates: A Technical Guide for Email Senders
Reducing unsubscribe rates with better consent, relevance, frequency, one-click headers, authentication, and suppression logic for healthier email delivery.
Oct 19, 202620 min read
On Hold Blocklist: What It Means, Why It Happens, and How to Fix It
Learn what an On Hold Blocklist means, why repeated soft bounces trigger it, how to troubleshoot delivery, and prevent future suppression.
Oct 18, 202620 min read
List Unsubscribes: How to Implement One-Click Opt-Outs
Implement the List-Unsubscribe header and RFC 8058 one-click POST flow, honor opt-outs quickly, and test every campaign for compliant delivery.
Oct 18, 202621 min read
How Transactional Emails Work: From App Event to Inbox
Learn how transactional emails work, from application events and APIs to SMTP delivery, DNS authentication, retries, bounces, and inbox placement.
Oct 18, 202624 min read
How to Request a Dedicated IP for Transactional Email
Learn how to request a dedicated IP, prepare DNS and authentication, pass provider review, warm the IP safely, and monitor deliverability.
Oct 18, 202622 min read
DMARC Monitoring: How to Read Reports and Fix Email Authentication
Learn DMARC monitoring: configure aggregate reports, interpret SPF and DKIM alignment, identify unknown senders, and safely enforce policy.
Oct 18, 202620 min read
Email Consent: A Technical Guide for Developers
Email consent helps developers send wanted mail, preserve deliverability, document opt-ins, honor revocations, and separate marketing from transactional email.
Oct 17, 202620 min read
Build a Journey for a Purchase Anniversary
Build a purchase anniversary email journey with reliable event data, scheduling, personalization, suppression, authentication, and delivery monitoring.
Oct 17, 202622 min read
How to Add SPF, DKIM, DMARC, and Return-Path Records in Strato
Learn how to add SPF, DKIM, DMARC, and Return-Path DNS records in Strato without breaking mail delivery or domain verification.
Oct 17, 202620 min read
How to Add SPF, DKIM, DMARC, and Return-Path Records in GoDaddy
Complete GoDaddy SPF DKIM DMARC setup: add sender-authentication and return-path DNS records, avoid common host-name errors, and verify delivery.
Oct 17, 202619 min read
SMTP Relay: How Does It Work? A Practical Setup Guide
Learn how SMTP relay works, from message submission and DNS routing to TLS, authentication, SPF/DKIM/DMARC, testing, and troubleshooting.
Oct 4, 202620 min read
SMTP: What It Is and How It Affects Email Deliverability
Learn what SMTP is, how the email-sending protocol works, which SMTP errors matter, and how to improve deliverability for every message.
Sep 26, 202624 min read
What Is DMARC? A Practical Guide to Email Authentication
What is DMARC? Learn how email authentication, domain alignment, policies, and reports protect your domain and support stronger inbox delivery.
Sep 26, 202624 min read
Email Deliverability Troubleshooting: Why Inbox Placement Can Fail Unevenly
Email deliverability troubleshooting explained: identify provider-specific inbox drops, measure the right signals, and recover without guessing fast.
Sep 22, 202619 min read
Newsletter Domain Migration: How to Rebrand Without Destroying Deliverability
Newsletter domain migration can reset trust signals. Use this phased plan to authenticate, warm up, communicate the rebrand, and protect inbox placement.
Sep 20, 202620 min read
DMARC Record Options: Every Tag, Policy, and Setup Choice Explained
Learn every DMARC record option, including p, rua, adkim, aspf, sp, np, and reporting tags. Build, test, and enforce DMARC safely.
Sep 17, 202621 min read
Free Email Marketing Software: Definition, Limits, and Deliverability
Learn what free email marketing software includes, where free plans fall short, and how to protect deliverability as your list and sending grow.
Sep 16, 202622 min read
FBL Meaning in Email: How Feedback Loops Protect Deliverability
Learn the FBL meaning in email, how feedback loops report spam complaints, calculate complaint rate, and suppress recipients to protect delivery.
Sep 16, 202621 min read
Envelope From: What It Means for Email Deliverability
Learn what Envelope From means in email, how it affects bounces, SPF and DMARC alignment, and how to configure it for better deliverability.
Sep 15, 202622 min read
Email Warmup: How to Build Sender Reputation Safely
Email warmup explained: learn how gradual, consent-based sending helps new domains and IPs build trust, protect deliverability, and avoid spam.
Sep 15, 202623 min read
Email Spoofing: Definition, Examples, and Prevention
Email spoofing is forged sender identity in a message. Learn how SPF, DKIM, and DMARC help stop impersonation and protect deliverability.
Sep 14, 202623 min read
Email Service Providers: Definition, Types, and Deliverability Impact
Learn what email service providers are, how they differ from mailbox providers, and how ESP choices affect sending, delivery, and reputation.
Sep 14, 202622 min read
Email Server: Definition, Types, and Deliverability Guide
Learn what an email server is, how SMTP, DNS, authentication, and reputation affect delivery, and how to keep campaign and transactional mail moving.
Sep 14, 202625 min read
Email Sender Reputation: What It Is and How to Improve It
Learn what email sender reputation means, what hurts it, how mailbox providers assess it, and practical steps to improve inbox placement.
Sep 14, 202621 min read
Email Noreply: Meaning, Deliverability Risks, and Better Alternatives
Email Noreply means an address that discourages replies. Learn how it affects trust, support, compliance, bounces, and deliverability—and what to use.
Sep 13, 202619 min read
Email Marketing 2: Definition, Deliverability, and Best Practices
Learn what Email Marketing 2 means, why it affects inbox placement and campaign performance, and how to build a permission-based program.
Sep 13, 202624 min read
Email Leads: Definition, Quality, and Deliverability
Learn what email leads are, how lead quality affects deliverability and campaign results, and how to collect, validate, segment, and nurture them.
Sep 13, 202623 min read
Email Header Explained: Fields, Authentication, and Deliverability
Learn what an email header is, which fields affect authentication and deliverability, and how to inspect, diagnose, and fix header issues.
Sep 12, 202626 min read
Email Compliance: What It Means for Senders and Deliverability
Learn what email compliance means, which legal and mailbox-provider rules apply, how it affects deliverability, and how to build a compliant program.
Sep 11, 202622 min read
E Mail Marketing Software: Definition, Features, and Deliverability
Learn what e mail marketing software is, how it supports campaigns and deliverability, which metrics matter, and how to improve email results.
Sep 9, 202626 min read
E Commerce Email: Deliverability and Campaign Performance Guide
Learn how e commerce email affects deliverability, revenue, customer retention, and campaign performance—and how online stores can improve it.
Sep 8, 202625 min read