Email Deliverability, Email Servers
Decode SMTP error codes: what 421, 450, 550, 552 and 554 mean, plus the Gmail, Outlook, Yahoo, Zoho and iCloud bounce codes - and how to fix each one.
Email Deliverability, Email Authentication
What is APRF? A new email standard that emails senders inbox-placement and engagement reports - like Google Postmaster Tools, but from any mailbox provider.
Email Security, Email Authentication
Public TLS certificate lifetimes are dropping from 398 to 47 days by 2029 - the 200-day cap is already in force. What it means for MX, MTA-STS, TLS-RPT and BIMI, and the 5-step plan to get ahead of it.
Email Deliverability, Deliverability Audit, Email Tools
Run a free email spam test in 2 minutes: send one email, get a deliverability score out of 10, and see exactly what to fix first. No signup - step by step.
Email Deliverability, Email Tools
An honest 2026 comparison of four free email spam testing tools - mail-tester, Unspam, MailChecker and Postbox Mailtester. What each checks, where each stops, and which to reach for when.
Email Deliverability, Email Authentication
Set up BIMI step by step - the DNS record, the SVG logo rules, VMC vs CMC certificates, and what Gmail, Yahoo and Apple Mail require in 2026 - plus how to get BIMI implemented if you would rather work with a consultant in India.
Email Deliverability, Email Authentication
The complete 2026 guide to Microsoft email deliverability: 15 bounce codes decoded, compauth/SCL headers from real captures, SNDS, escalation paths, and fixes per sender type.
Email Deliverability, Email Marketing, Email Security
Security scanners and privacy proxies inflate your open and click rates. How to tell real from bot opens and clicks, and measure genuine human engagement.
Email Authentication, Email Deliverability, Email Security
A DKIM replay attack re-sends one validly signed message to millions and it still passes. How replay works, a safe lab to see it, and how DKIM2 fixes it.
Email Authentication, Email Deliverability, Email Security
A provider dropped an unreadable XML file in your inbox? Here is what a DMARC aggregate report is and how to read one, field by field, with a worked example.
Email Security, Email Deliverability
Anyone can fake a sender name - the email headers are the receipts. Learn to read Authentication-Results and the Received chain to catch a spoof in seconds.
Email Deliverability, Email Security
TLS-RPT tells you when senders cannot reach your mail server securely. Learn how it works, what the reports mean, and the safe order to set up MTA-STS without breaking your email.
Deliverability Audit, Email Authentication, Email Deliverability
Run a free email domain health check and understand every result. MX, SPF, DKIM, DMARC, MTA-STS, TLS-RPT, BIMI and DNSSEC explained simply, with the...
Email Deliverability, Email Tools
Google Postmaster Tools now shows plain-English verdicts like "users don't want your email." See all 7 reasons, real screenshots, and what they mean.
Learn how to implement SPF, DKIM, and DMARC to protect your domain from email spoofing. Complete step-by-step guide with examples and best practices...
B2B Emails, Cold Emails, Deliverability Audit
Old play books and purchased lists are killing your deliverability. Learn how adaptive B2B email systems deliver inbox placements and replies in 2026.
Learn how to set up your email sending domain on GoHighLevel. Improve email deliverability with step-by-step DNS setup.
If you're struggling with low open rates it's time to look 6 Strategies to Control Your Spam Complaint Rates
Cold Emails, Email Deliverability, Email Tools
Are email warmup tools still effective in 2025? We tested all major providers and found most show no real improvement in deliverability or domain...
Stay ahead of the 2025 email tracking and privacy regulation changes. Learn how Gmail, Apple, and Microsoft are altering email tracking, why open rates...
Learn how to create a catch-all in Microsoft365 using mail flow rules, configure MX records, and change domain status to Internal Relay. Ensure no...
Discover the latest cold emailing strategies for 2025! Learn what works and what doesn't, from email sequencing and delivery streams to campaign...
Deliverability Interview Series, Email Deliverability, Interviews
Bouncer is an easy to use and easy to integrate email verification solution.. Read our deliverability interview with Radek from Bouncer.
Deliverability Interview Series, Email Deliverability, Interviews
In interview 5 of the deliverability interview series we spoke to Sebastian Kluth from Certified Senders Alliance.
Deliverability Interview Series, Email Deliverability, Interviews, Technology
Interview with Anders Berggren about Halon - a large scale MTA, its features and how it helps with email deliverability.
Deliverability Interview Series, Email Deliverability, Interviews
Read this interview to understand how a good domain warmup tool like Mailreach can help you achieve email deliverability
Deliverability Interview Series, Email Deliverability, Interviews
Interview with Arun Kumar from Zoho Campaigns team. Arun talks about various aspects of email deliverability and how Zoho has implemented these practices.
Deliverability Interview Series, Email Deliverability, Interviews
Interview with Przemysław Kuciel from Omnisend about different email deliverability challenges and best practices.
Do you feel constrained with Salesforce CRM's email marketing capabilities. See this review of MassMailer a native Salesforce app.
Do you know what different types of lead nurturing campaigns you can run? Read this detailed articles to find out.
Cold Emails, Email Deliverability, Interviews
Interview of Ajay Goel, founder of GMass on secrets of cold emails and the journey of GMass.
Email Deliverability, Interviews
An exclusive interview of Vaibhav Namburi on how Smartwriter came in to being and how it is helping people achieving deliverability.
Do you understand what lead nurturing is and how to start nurturing your leads. This article gives you all the details to nurture your leads.
Cold Emails, Email Marketing, Products
Mailshake Product Review: Mailshake helps businesses constantly stay in touch with a prospect with a multichannel approach
Do you know what is a landing page and how is it different from a web page? Do you know you can use Mailchimp for landing page?
Cold Emails, Email Deliverability, Products
Smartwriter is a personalisation outreach tool that helps to improve email deliverability - read this Smartwriter review.
Mailchimp guide to help you start email marketing with Mailchimp in 15 minutes. At the end of this guide, you will go from a Mailchimp beginner to an...
Step by step guide for cold emailing. Learn how to plan for cold emailing, what tools to use and the best practices
Email Tools, Products, Technology
Sendy is a very popular self hosted email newsletter tool. Let's see how to install it on Linux (Ubuntu and CentOS)
An exclusive interview with Alex Markov, CEO at G-Lock Software on achieving email deliverability with GlockApps
You often need to send tons of test emails during application development and you need a quick solution for that. Mailhog is the answer.
Email Deliverability, Email Tools, Products
GlockApps is a Swiss army knife for every email marketer to run an inbox placement test with a well covered seed list.
Deliverability Audit, Email Deliverability
At Postbox Consultancy Services we conduct a through email deliverability audit covering every minute aspect of your emailing
Cold Emails, Email Servers, Email Tools
This article explains how you can integrate your Gsuite with external SMTP to bypass GSuite daily sending limits.
GNU Mailman is an open source software for managing announcement and discussion lists and it belongs to GNU Projects.
Do you wonder if it is possible to monetize an automated email newsletter? This article will guide you about that.
For various reasons, you may be looking to set up catch-all on one or many of your subdomains. This blog has detailed instructions.
Email Security, Email Tools, Technology
Office 365 Message Encryption (OME): If you use emails to exchange sensitive information and think that the sensitive information may leak into the...
Email Marketing, Email Tools, Products, Technology
Mailwizz is a fully-featured self hosted email marketing application. It has unique features to improve deliverability.
Inactive email subscribers can be detrimental. Focus to identify and manage inactive email subscribers to create correct email list segments.
Welcome emails are very important to connect with the subscriber. Let's learn the top 10 best practices for welcome emails
Email Deliverability, Email Design, Email Marketing
This blog post discusses the best practices to design a good looking and highly engaging email newsletter template.
Why do you get low open rates on your email marketing campaigns? This blog hast steps to improve your email campaigns open rates
Cold Emails, Email Deliverability, Email Marketing
Plain text vs HTML emails. Let's dive in to the details and see which one should be used in which scenario.
Do you have to choose between email marketing and social media marketing? You would be surprised how integrating social media into a killer email...
Let's see what is an email footer, what is its importance and what are the top 7 best practices for email footer design
Cold Emails, Email Deliverability, Email Marketing, Email Tools
Recipients check the Gmail's promotions tab with less interest. How to land in gmail inbox's primary tab. Let's find out.
Email Servers, Products, Technology
Zimbra (ZCS)Â is an open source and free for personal use, collaborative software platform. Let's see how to install it on Ubuntu 18.04
The three primary goals of an email marketing funnel are to educate, nurture, and nudge. Let's learn more about an email marketing funnel.
Cold Emails, Email Deliverability, Email Marketing
A cold email is an email you send to someone who is a business prospect but stranger to you. Here are 15 pro tips to write cold emails.
Deliverability Audit, Email Deliverability, Email Marketing, Email verification
Do you know the significance of an email deliverability manager or email deliverability agency? Read this blog to find why you might need one
SMS campaigns have a 98% open rate. With only 39% of marketers using SMS, this could be an untapped avenue for direct, targeted political campaign messages.
Political campaign emails can help senders build relationships with their communities by sending personalized content.
An exclusive interview with Cathy Patalas, Woodpecker’s Chief Growth Officer. Patalas has been with the company since the start in 2015
Woodpecker Review - A Tool To Save Time in Cold Email Outreach by Quick Automation. They have a great academy to learn cold emailing.
Email verification, Email Deliverability, Email List Cleaning
Do you know what is email list cleaning or email list hygiene? Read this anatomy of email list cleaning | A complete what, why, how and where
Postbox Services has developed this email deliverability checklist after studying and researching all email deliverability best practices
How to shift your email marketing message during difficult times. After COVID lock downs now is the time to update your email copy.
Replyify Review - Replyify helps to automate cold email outreach while still allowing you to personalize as much as possible
Social proofs can be used in email marketing. It helps in improving campaigns credibility and email deliverability. Let's learn how.
Are you struggling with your email marketing conversion rates? Let us help you with these 15 tips. Included a deliverability checklist.
This article tells you 5 things you need to keep in mind while planning your email campaigns to announce new products after lock down.
Email drip campaigns are used to connect with customers individually and repeatedly with the help of an autoresponder.
Email verification, Email List Cleaning
Email verification or email list cleaning is an important step in maintaining a healthy email list. Let's learn the importance of email verification
Do you know you can send confidential emails in gmail? If not read this article. The article has details of different modes to secure email.
If you are facing any email deliverability issues and need help please contact us.
One of the more useful features that were available on many other email providers, but not Gmail, was sending multiple emails as attachment in a single...
Holiday season is a rush for email marketers and this rush leads to many mistakes. Let's learn how to avoid these email marketing mistakes.
Email Authentication, Email Deliverability
Let's learn about ParseDMARC. An open source DMARC analyzer - alternative to commercial DMARC report processing tools.
Email Marketing: Year in review 2019 and what is in store for 2020. AMP for email will be the latest rollout.
AMP for Email in 2020: Is your email marketing program ready for dynamic emails? Let's learn more about AMP for email
Do you know what are the 10 things to keep in mind while designing your abandoned cart emails series. Let us find out.
Steps to install iRedmail on Ubuntu 18.04. iRedmail is an open source email server which is very easy to install and configure.
Email Deliverability, Email Marketing
Black Friday and Cyber Monday email marketing preparation. Let's learn about all best practices to follow to get best email deliverability.
What is a feedback loop and why should you be signing it up while setting up your bulk emailing system. Let's dive in to details.
Email Authentication, Email Deliverability, Email verification
An SPF (Sender Policy Framework) record is used to indicate which hosts are authorised to send emails for a domain. It is defined in RFC 4408 and...
Email Authentication, Email Deliverability
DMARC stands for “Domain-based Message Authentication, Reporting & Conformance.”  DMARC is built upon two other authentication protocols: SPF (Sender...