Every domain should have working abuse@, postmaster@ and security@ addresses and a security.txt file. What RFC 2142 and RFC 9116 ask for and a 20-minute setup.
September 2, 2026
ARC lets a forwarder or mailing list record and sign the authentication results it saw. Learn what ARC is, why forwarding breaks SPF, and how to read it.
August 24, 2026
List-Unsubscribe is a header that lets mail apps show an unsubscribe button. Learn how RFC 8058 one-click works and why Gmail and Yahoo require it. Learn…
August 22, 2026
A feedback loop reports back when a recipient marks your email as spam. Learn what an FBL is, how spam complaint rate is measured, and how to stay under 0.3%.
August 20, 2026
IP warming means raising sending volume from a new IP gradually so receivers build trust. Learn what IP warming is and when a small business can skip it.
August 18, 2026
Sender reputation is the trust receivers assign to your sending domain and IP from past behaviour. Learn domain vs IP reputation and how to build it. Learn…
August 16, 2026
Email encryption in transit explained in plain language: how TLS and STARTTLS protect mail between servers and apps, what they do not protect, and how to check.
August 15, 2026
A spam score is the total of many small tests a filter runs on an email: content, reputation and authentication. Learn what a spam score is and what moves it.
August 14, 2026
A DNS blocklist (DNSBL) is a list of IPs or domains tied to spam that mail servers query over DNS. Learn how listings happen and how to check if you are…
August 12, 2026
Dangling DNS records and subdomain takeover explained: how leftover CNAME, MX and SPF entries from cancelled services let attackers send as your domain.
August 12, 2026
Protect your domain from hijacking with four registrar settings: transfer lock, two-factor authentication, auto-renew with a valid card, and WHOIS privacy.
August 10, 2026
Lookalike domains and typosquatting explained for small businesses: the variants attackers register, how to monitor for them, and practical defences that work.
August 8, 2026
The Return-Path is the address that receives bounces for an email. Learn what a Return-Path is, how it is set from MAIL FROM, and how bounces get back to you.
August 4, 2026
The envelope From (MAIL FROM, Return-Path) is where bounces go; the header From is what people see. Learn why they differ and which one SPF and DMARC check.
August 2, 2026
DKIM key rotation for small businesses: why keys should be replaced, a realistic schedule, and a two-selector method so nothing bounces during the switch.
July 22, 2026
How to add third-party senders like Mailchimp, HubSpot and Shopify to your SPF record safely, count DNS lookups, and stay under the 10-lookup limit.
July 20, 2026
Read a raw DMARC aggregate report (rua) by hand: what each XML field means, which rows show spoofing versus a misconfigured sender, and how to open .gz files.
July 17, 2026
Move your DMARC policy from p=none to quarantine to reject in 30 days without losing legitimate mail. Exact TXT record values for each stage and what to check.
July 15, 2026
What "SPF PermError: too many DNS lookups" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "550 5.7.1 message rejected due to SPF" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "DKIM signature did not verify" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "DMARC fail / message rejected by DMARC policy" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "421 4.7.0 temporarily rate limited" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "550 5.1.1 user unknown / recipient rejected" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "my email goes to spam in Gmail" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "Google & Yahoo bulk sender requirements" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "454 4.7.0 cannot authenticate / SMTP auth failed" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "connection timed out on port 25" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "MX record not found / no mail server for domain" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "soft bounce vs hard bounce — what to do" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "SPF: none (no SPF record found)" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "no DMARC record / DMARC: none" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "reverse DNS / PTR does not match" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "email delayed by greylisting" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "too many recipients / 452 4.5.3" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "my domain or IP is blacklisted" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "SPF vs DKIM vs DMARC explained" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "From address looks like spoofing / via warning" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "should I use a catch-all address" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "not receiving any email on my domain" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "attachment too large / message size exceeds limit" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "SSL certificate error connecting to mail server" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "how long until my email DNS records work" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "more than one SPF record found" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "should I send from a no-reply address" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "Gmail shows a red question mark on my sender" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "552 mailbox full / over quota" means and exactly how to fix it — with the DNS or client change that resolves it for good. Practical guide for…
July 5, 2026
What "STARTTLS not supported / must issue STARTTLS first" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "email still delivering to my old provider" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
What "OquMail domain verification stuck on pending" means and exactly how to fix it — with the DNS or client change that resolves it for good.
July 5, 2026
Data processing, subprocessors, and practical steps for GDPR-conscious teams choosing email hosting for @yourcompany.eu domains. Practical guide for…
June 16, 2026
Gmail tabs, engagement signals, and authentication — fixes for legitimate senders. Practical guide for non-technical small business owners.
June 16, 2026
What counts as a complaint, acceptable thresholds, and how one bad list hurts everyone on your domain. Learn spam complaint rate in plain language.
June 16, 2026
Temporary failures vs permanent — how to read SMTP codes and clean your lists. Learn soft bounce hard bounce in plain language. Practical guide for…
June 16, 2026
Week one to month three — what to expect when your domain has no sending history. Learn new domain email reputation in plain language.
June 16, 2026
XML reports demystified — who sends as your domain and whether authentication passes. Learn DMARC reports explained in plain language.
June 16, 2026
Authentication, content, lists, and volume — practical deliverability without an ESP enterprise contract. Learn avoid spam folder business email in plain language.
June 16, 2026
Why noreply@ hurts deliverability and what to use instead for transactional messages. Learn reply-to address best practices in plain language.
June 16, 2026
What authentication failures mean in headers, common misconfigurations, and copy-paste fixes for small business domains. Learn SPF failure in plain language.
June 15, 2026
Catch-all addresses collect spam and hide bounces. Learn safer patterns for startups that want every name@ to work. Practical guide for non-technical small…
June 15, 2026
DNSBLs, spamhaus listings, and remediation steps for small businesses — prevention via authentication and hygiene. Learn email blacklist check in plain language.
June 14, 2026
Sending volume ramps, authentication checks, and mistakes that burn a fresh domain — for startups sending their first real campaigns. Learn email domain…
June 13, 2026
Receipts, password resets, and newsletters are not the same — authentication, volume patterns, and why to separate them. Learn transactional vs marketing…
May 26, 2026
Hard vs soft bounces, complaint rates, and how OquMail's deliverability dashboard helps you spot problems early. Practical guide for non-technical small…
May 17, 2026
Fifteen checks before you send marketing or transactional mail — DNS, content, lists, monitoring, and bounce handling. Learn email deliverability checklist…
May 11, 2026
Authentication failures, reputation, content signals, and list hygiene — a practical checklist to get back to the inbox. Learn emails going to spam in plain…
May 4, 2026