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Deliverability

Zeqo guides in the Deliverability category, organized for faster browsing.

DeliverabilityDKIM

Microsoft 365 Email Authentication: SPF, DKIM & DMARC Setup Guide

Microsoft 365 doesn't sign with DKIM properly until you enable it per domain — and the CNAME setup trips almost everyone. Here's the full sequence.

8 min read
DeliverabilitySPF

Can You Have Two SPF Records? (No — and Here's How to Merge Them)

Adding a second SPF record doesn't add senders — it invalidates both. Here's the rule, and the correct way to merge.

5 min read
DeliverabilityBlacklists

Spamhaus Blacklist: How to Check, Understand, and Get Delisted

Spamhaus is the blocklist that actually matters. The delisting process is free and fast — if you fix the cause first.

6 min read
DeliverabilityEcommerce

Klaviyo Deliverability: Sending Domain Setup and Why Emails Go to Spam

Klaviyo's default shared sending domain means you inherit other senders' reputation. Here's the correct setup and the usual culprits behind spam placement.

7 min read
DeliverabilityComparison

Zeqo Mail vs MXToolbox: Which Should an Agency Actually Use?

MXToolbox answers “what does this record say right now?” Zeqo Mail answers “which of my 30 client domains broke this week?” They're different jobs.

6 min read
DeliverabilityComparison

Zeqo Mail vs dmarcian: DMARC Depth or Portfolio Coverage?

dmarcian goes deeper on DMARC than almost anyone. Zeqo Mail goes wider across domains and checks. Here's how to pick.

6 min read
DeliverabilityComparison

Zeqo Mail vs EasyDMARC: A Practical Comparison for Agencies

EasyDMARC gives you a full platform. Zeqo Mail gives you a scored portfolio and a fix to paste. Which one matches how you actually work?

5 min read
DeliverabilityDMARC

The Best Free DMARC Tools in 2026 (Generators, Checkers, Analysers)

Free DMARC tools fall into three groups that solve three different problems. Here's which to use when, and where each free tier runs out.

7 min read
DeliverabilityDKIM

What Is My DKIM Selector? How to Find It (Provider Lookup Table)

Your DKIM selector is the prefix in the DNS lookup — and most providers use a predictable default. Here's the table, and how to find yours if it isn't listed.

6 min read
DeliverabilityDMARC

DMARC Policy: When to Use p=none, quarantine, or reject

A DMARC record at p=none monitors but protects nothing. Here's when to move to quarantine or reject without breaking your own email.

8 min read
DeliverabilityTransactional email

Transactional Email Deliverability: Keep Password Resets and Receipts Out of Spam

Password resets, receipts, and product alerts cannot wait in spam. A practical deliverability checklist for transactional email.

8 min read
DeliverabilitySPF

SPF Record Syntax Explained: Includes, IPs, and the 10-Lookup Limit

SPF looks like one TXT record, but includes, redirects, and the 10-lookup limit can quietly break all your mail. Here's how to read it correctly.

8 min read
DeliverabilityDKIM

What Is a DKIM Selector? (And Why “DKIM Missing” Is Often Wrong)

Half the “your DKIM is missing” warnings are false alarms. The reason is the selector — what it is, where it lives, and how to check yours correctly.

7 min read
DeliverabilityGoogle Workspace

How to Set Up SPF, DKIM & DMARC for Google Workspace (Step by Step)

New on Google Workspace? Here's the exact, copy-paste setup for SPF, DKIM, and DMARC — plus how to confirm all three actually pass.

8 min read
DeliverabilityReputation

Email Warm-Up: How to Build Sender Reputation Without Hitting Spam

Send 500 emails from a brand-new domain and you look exactly like a spammer. How to warm up the right way — and the ramp schedule to follow.

8 min read
DeliverabilityDMARC

DMARC Reports Explained: How to Read Them and Fix What They Reveal

Set up DMARC and the reports start rolling in — as unreadable XML. What they actually tell you, and how to use them to lock down your domain.

8 min read
DeliverabilityDNS

SPF, DKIM & DMARC Explained: A Plain-English Guide for Founders

The three DNS records that decide whether your email lands in the inbox — explained without the jargon, plus how to check yours in 30 seconds.

8 min read
DeliverabilityCold email

Why Your Cold Emails Land in Spam (and How to Fix It)

Authentication is only half the battle. The real reasons outreach gets filtered — and a checklist to land in the inbox instead.

9 min read
DeliverabilityBlacklists

How to Check if Your Domain Is Blacklisted (and Get Delisted Fast)

A blacklisting can block your email overnight — without any warning. How to find out if you're listed, get removed fast, and avoid it happening again.

7 min read
DeliverabilityCompliance

Google & Yahoo Sender Requirements: The Checklist Every Sender Needs

Since 2024, Gmail and Yahoo enforce real rules for senders — miss them and your mail gets rejected. The complete checklist, explained simply.

7 min read