Do you know that Gmail affects your deliverability?

In February 2016 Google stated that it had over one billion active Gmail users, a news unthinkable when years earlier the first e-mail was sent. In 2019, it confirmed itself as the first e-mail client used in the world with a market share of almost 30%, and the other e-mail providers being separated by many percentage points – the only exception is Apple iPhone, which moved hand in hand, but that’s history unto itself.

So we can safely say that even among your contacts, we find a significant number of people using a Gmail e-mail address. And that’s why Google takes care of its customers.

Gmail in fact daily updates the e-mail filters and thinks them to protect the boxes as much as possible. How? Mostly by monitoring and reacting to users’ actions towards the e-mail communications they receive.

So it becomes important for brands that want to use e-mail as a contact channel, follow some best practices that also arise from the analysis of Gmail’s own behavior towards e-mail.

Brand objective: to maintain the reputation of the domain at the highest level and allow your e-mails to reach the inbox of the largest number of contacts.

Gmail deliverability

What can you do to increase the delivery rate of your e-mails to Gmail accounts?

To prevent your e-mails from being blocked and placed in the spam folder, you need to follow some precautions. There are several areas to work on, some in charge of brands, others to any ESPs that support you in marketing communication activities. Let’s try to see some of them together. It is not an exhaustive analysis but there are good ideas to improve delivery rates, opening and reading of e-mails. Let’s start.

Always use the same IP Address to prevent Gmail from classifying you as a new sender and you need to rebuild your reputation all over again. In case you have to use more than one, associate each IP address to different types of communications: service, promotional, newsletter, etc.. And in this regard, the suggestion is also to keep the same header: from for e-mails of the same categories.

In any case, remember to rationalize the tests you sent that often have a negative impact on the reputation of your domain and pay attention to the volumes: increase them gradually and monitor the situation with Postmaster tools to move immediately in case of critical issues. Above all, the initial phase of new deliveries requires a lot of attention, the so-called onboarding phase, i.e. the phase in which you start using new lists. While a bad reputation is unfortunately achieved in very few wrong moves, a good reputation is built with time and effort. And Gmail is very strict in this respect.

Keep the contents of your communications as consistent as possible, don’t mix extremely different messages in the same e-mail, and watch out for the domains in the entire message – even for images for example – because to define reputation, Gmail considers everything. Also, keep the e-mail format as close to standards as possible, but for this you can contact our consultants.

Another thing, perhaps even one of the most important. Remember when we recently talked about e-mail authentication? SPF, DKIM and DMARC?

Well, Google pays attention to these aspects and has been one of the first providers to use SPF and DKIM on messages. It was also one of the major contributors of DMARC. It protects its users from potentially illegitimate e-mails by relying on such protocols and for brand domain reputation systems. Ask us how to do it and we can support you in this fundamental step.

And then, be careful, as we said before Gmail trusts its users blindly, it monitors their behavior in the management of e-mails and for example, if some of them have not explicitly chosen to read your communications, they will most likely end up in the Spam box. If your e-mails start to be recognized as unwanted, it will happen more and more often in the future with devastating effects on your reputation as well as the success of individual campaigns.

Take it as a good practice to always opt-in to your e-mails – but don’t use forms with pre-filled permissions, let your contact decide and feel free – and give them the opportunity to unsubscribe. If your brand relies on an ESP, make sure that boxes are set up to handle abuse reports and that you constantly monitor all requests from your contacts, including updating their data. Contactlab also provides this service.

Do not rely on lists collected and sold by third parties, on the contrary, segment. Address more and more refined audiences. For example, Gmail reduces spam rates to those domains that have higher e-mail opening rates. Make sure that your contacts include your brand among the desired senders and do not report you as spam.


The variables you need to work on to keep your domain’s reputation high and ensure the best possible delivery rates even for Gmail users can be grouped into macro-areas:

  • IP Address.
  • Authentication.
  • Engagement.
  • Opt-in.
  • Format.

Don’t waste time then, every delivery could be a missed opportunity – or worse – if you don’t follow the best practices Gmail requires. Call us and our deliverability experts can study an action plan tailored to your brand and the characteristics of your contacts and deliveries.

Contactlab has the right solution to your needs thanks to technology and experience.

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Is an excellent e-mail delivery tool enough for the success of your campaigns?

Well, it’s done. You’ve choosen the Contactlab platform for your e-mail campaigns. Now? What other steps are essential to make your deliveries effective, the e-mail arrive in the inbox and the contacts engaged?

The value of a good database

Whenever we face with the activation of a new sender or the request to use a new database, our deliverability experts are ready to suggest some valuable and useful indications to improve the quality of the data and consequently the result of the deliveries.

Sending e-mails means configuring all technical aspects of the delivery but also taking care of the lists to be addressed and therefore the reputation of the sender – your brand. A bad reputation in fact very soon leads to being filtered, or worse, blocked, by the main recipient domains and this reduces the effectiveness of any e-mail activity.

While a bad reputation is unfortunately achieved in very few wrong moves, a good reputation is built with time and effort. Recovering a ruined reputation is much more difficult, expensive and uncertain than keeping it good by paying attention over time.

That’s why getting off on the right foot with a new database is very important. Among our proposals that go in this direction, we find the Vetting and Boarding procedures.

What is the Vetting

A qualification process: a simple questionnaire submitted to the brand on the database – and on the e-mail flow, to be filled in before any delivery addressing it. In this way, our experts are provided with information that enables them to complete the analysis independently and at different levels. The aim is to identify the best:

  • Technical configuration: from the implementation of dedicated or shared IPs to dedicated sender domains or tracking links in the e-mails.
  • How to start using the database or e-mail flow: for example the Boarding process that we will see in detail below.

For this phase to give a really useful result, it is necessary that the indications provided by the brands are complete and as correct as possible, otherwise the effectiveness of the whole analysis is compromised.

What is the Boarding

Boarding example


This is the phase that in the example above precedes the date of April, 15th and which puts resources into place to improve the KPIs of your e-mail campaigns. The chart shows the impact of the procedure: the opening rates on the receiving domains reflect a fluctuating movement that is stabilized over time by using targeted tasks under the guidance of our experts. If you are interested to know what actions have been taken in this individual case, please contact us.

It is essentially a risk reduction procedure caused by the use of a new database of uncertain quality, the duration of which depends on the results obtained during its execution.

The main aim is to identify any critical points and discover the best ways to manage or limit them, thus avoiding that new lists cause irreparable damage to the sender’s reputation due to massive or careless use.

How it works

The database is first sampled on a statistical basis and then segmented into tranches whose size is determined by the sampling result.

Both the initial sample and the subsequent tranches are then included regularly in e-mail campaigns:

  • No more than one per day per recipient.
  • For a period whose duration depends on the size of the database, on the sampling results and on the continuous monitoring of regular deliveries downstream of the sample.

The relevant phenomena initially assessed and then measured and reconsidered during the trial includes:

  • The information gathered in Vetting.
  • Hard bounce rates – i.e. invalid addresses – and their deviation from best practice values.
  • Spam rates and abuse reports.
  • Positive engagement rates: openings and clicks.
  • The result of spam filters analysis on messages sent during the Boarding phase.
  • The result of the Inbox Placement observation.
  • The distribution to the target domains.

In most cases the procedure is short and the brand can start sending. In other situations, however, more time is needed to reach a verdict that is perhaps below expectations. However, ignoring any problems is not the best way to proceed. The stakes are high and the benefits of such an approach are very clear.

What can Boarding reveal?

The results can be varied and very different. In the worst case a database can be unusable but also require:

  • Special actions such as the re-optin of the entire database.
  • Split into segments of different quality.
  • Reactivation initiatives.
  • The elimination of problematic segments due to e.g. original data collection mode or obsolescence.
  • The adoption of a different startup approach on different segments.
  • The use of differentiated dedicated IPs.


Whatever the outcome, these procedures offer precise indications to be implemented and tailored to the specific needs of the brand at that particular time. It is a teamwork that starts and goes from the constant collaboration between the brand and Contactlab.

Contact us now. We’ll see together how Contactlab Marketing Cloud and the expertise of a team of experts can help you to design and implement successful marketing campaigns to support your business.

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Email at the time of #covid19: a safe way to get to your customers’ homes

If your customers can’t come to you, you go to them… digitally! Review the way you do email: from content creation to feedback management. Choose the right partner for this new adventure.

welcome home

Pack your consumer dream email!

Take care of all the contacts who might be interested in your brand.

Who is not a customer yet. You have huge amounts of data also about them, their demographic characteristics, their preferences, their behaviors…it’s time to use all this information and do it well to reach them and try to bring them on board. Now more than ever, people at home have time to make new experiences. Explore all the data and figure out how to hit them on the first try. Maybe a welcome discount can convince even the most hesitant of the customers to finally buy the latest model of television he has so longed for in the past so he can enjoy subscribing to streaming TV service during this quarantine period.

Who’s been out of touch for some time. What happened to someone who used to be a loyal customer? Take the time to study them, see if in the past you may have underestimated any aspect of your relationship and see how to resume it. You may find that you’re promoting infant formula, with convenient same-day home delivery free of charge, to customers who told you they had children more than 3 years ago.

Who keeps buying but with low spending level. Try offering him a survey, for example, now maybe he has time to dedicate to you. Understand if he also relies on other brands or better know what you could do for him to increase his trust and value for you. Maybe he’s a recurring buyer on a single product or service. He simply hasn’t had any incentive to browse your ecommerce and find out there are plenty of other purchase options for him.

Who confirms himself a Top Spender. Don’t forget them, they appreciate all your sales channels but maybe they might miss your store. Don’t abandon him, keep him engaged with communications that give value to your offer and your relationship that must continue to grow even if physically distant.

How to create eye-catching emails especially now that many brands are using the email channel to talk to their customers? How to stand out? What not to forget?

Try putting yourself in your customers’ shoes.

Think about what you would appreciate from brands in these days when moving around freely has become difficult. You might want to read…

…what interests you most

email #covid19

Emails tailored to your real needs and requirements. Collecting all the information about your contacts, processing and integrating all the data and creating a unique profile for each of them, allows you to have what you need to pack personalized emails and to address targeted audiences with similar characteristics. For example, you can decide to send special discounts on specific products to those who have concluded online purchases in the last month, changing the value based on the total expenditure made in the past.

…comfortably seated on your couch

email #covid19

Emails straight into the inbox wherever you are. Entrust your deliveries to a sending engine that guarantees maximum delivery rates and make sure that the recipients of your communications receive your messages. Ensure the support of a team of experts who can guide you in your deliverability strategies to better manage especially security issues such as DMARC.

…whenever you want

email #covid19

Emails reach you at the appropriate time. Choose email triggers that go off when an event occurs – for example when a contact forgets a product in their shopping cart when it expires – or automations that go off when the purchase is finalized to keep the customer updated on his order at every change of status.

…on the device you prefer

email #covid19

Emails built to be displayed on multiple devices without losing any items. Choose email editors that let you decide what you want your readers to view depending on the device they are using and give you the possibility to create responsive email designs to fit perfectly on any screen.

..that it’s something that gives pleasure to your eyes

email #covid19

Team of consultants that can design and realize the best email structure and the correct graphic representation of your message, capturing every nuance of your relationship, starting from your offer and the deepest knowledge of your customers.

Contactlab can offer all this

The excellent technology offered by the Marketing Cloud (smart)Platform and the team of consultants able to support you in building unforgettable customer journeys are the winning solution for you. They are the answer to your needs and allow you to tiptoe into your customers’ homes in these days of forced isolation.


You decide to stay close to your customers and continue to offer them the best customer experience possible. Support your business with constant and personalized customer engagement campaigns so they don’t feel alone in this moment of physical distance.

Contact us and we’ll see the enormous value you can get from combining the Marketing Cloud and Digital Marketing Services offered by professionals in this field for decades. Let’s try to stay close though social distancing, together we can try to overcome it in an easier way.


#covid19 en

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DMARC: Do Mailbox Providers apply it to the letter? Here they are some feedbacks from real experiences

A few days have passed since the last Send releases in the security area and the platform has further enhanced functionality to ensure high inbox placement rates more and more.

The growing threats we see daily in the world of e-mail marketing – domain spoofing, phishing, spear phishing, etc.. – have accelerated the adoption of brand protection tools. In addition to the historical SPF and DKIM methods, DMARC is gaining a strong foothold in recent months.

DMARC is based on SPF and DKIM and helps the Sender – often the brand, and the Receiver – or the Mailbox Provider, to determine whether a message has been sent legitimately or not.

DMARC can therefore have an important impact on the deliverability of your e-mail campaigns.

How it works briefly

The legitimacy is determined by the Sender through the so-called mechanism of the alignment between the domain in From with the DKIM and/or SPF signature. In short, the brand which sends explicitly tells the Mailbox Provider which receives whether an e-mail is legitimate. Alignment in DMARC jargon means that the two must be equal.

The implementation of DMARC requires a progressive approach with several control steps. Moving immediately to a restrictive policy, without the right conditions, can cause quickly visible spam and deliverability problems.

For more on DMARC’s operation and alignment concept, read here.

How to protect e-mail deliveries

In case of DMARC not aligned, the brand can ask the Mailbox Provider to apply different policies:

  • p=none → do not apply any policies and do not take any actions with the e-mail in error.
  • p=quarantine → mark the non-aligned e-mail as spam.
  • p=reject → reject the e-mail.

However, we are experiencing how the major Mailbox Providers do not always apply the policy as stated by the Sender.

Let’s see an example together.

How do the main Mailbox Providers behave?

If the Sender sets the policy in quarantine without aligning the From and the domain of the DKIM signature, what we expect is that the Mailbox Providers will filter the e-mail directly into the spambox, following the Sender’s instructions.

And in a not aligned context, we should get such an effect:


That is, e-mails should simply go into spam, inbox placement worsen and consequently decrease the open rate. Or at least that’s what the brand would expect.

Looking at some delivering experiences – one of many in the chart below, we see that the situation in the real world is more complex: different Mailbox Providers behave differently with the same DMARC policies set by the brand.

This makes any analysis more complicated when the inbox placement lower abruptly.


The Contactlab platform provides the tools to monitor the reaction of the top five Mailbox Providers to policy changes in a not aligned DMARC context.

In the Control section of Send you can check after DMARC changes:

  • Which Mailbox Providers follow the DMARC policy by setting timely reactions. The open rate levels suddenly drop to 0%, the e-mail is filtered in the spambox, as required by the p=quarantine policy. These include Yahoo! and Gmail.
  • Which Mailbox Providers do not show obvious repercussions on e-mail performance. The open rate trend is practically constant. These include Libero and Alice.
  • Which Mailbox Providers use the not aligned DMARC information to feed their antispam algorithms but do not directly put the e-mail into spam. The open rate trend is definitely downward, without vertical collapses and will recover when the p=none policy returns. It falls within these Hotmails.


DMARC is becoming more and more popular with brands because it guarantees the reputation, a good brand visibility also thanks to the support of BIMI, prevents domain spoofing…but to get the most out of it, especially in terms of deliverability, it must be implemented with a special focus.

Contactlab offers the tools to set up a control activity and to be able to constantly monitor that deliveries take place in the best conditions, that everything is managed in a structured way, that there is a correct setting of e-mail parameters and that the performance of deliveries maintain the highest levels.

This is also thanks to the presence of a team of deliverability experts who represent the perfect partners to analyze the punctual situation of your brand, the characteristics and results of your deliveries, and suggest you how to move to maximize the delivery rate of your e-mails, prevent negative situations and immediately improve the effectiveness of your marketing campaigns.


#covid19 en

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A top-notch e-mail reputation to bring deliverability at the highest levels!

Domain Authentication: limits and developments

A new message!The authentication of the sender’s domain is increasingly important in the world of e-mail. Threats such as domain spoofing, phishing and spear phishing have encouraged the development of stronger authentication strategies for brands. Protocols such as SPF – Sender Policy Framework and DKIM – DomainKeys Identified Mail, have started showing some pitfalls. It becomes fundamental to think about adding new check methods, first of all DMARC.



Based on SPF and DKIM usage, DMARC extends their value:

  • to safeguard brand’s reputation and its customers
  • to protect the business
  • to enable the GDPR compliance

Furthermore DMARC brings benefits to deliverability. It is now clear that the adoption of DMARC with a restrictive policy positively influences the score of the major mailbox providers, starting from Gmail which explicitly suggests it in the bulk senders guidelines.

A restrictive DMARC policy is also necessary for the implementation of the BIMI – Brand Indicators for Message Identification – i.e. showing the official brand logo directly in the inbox. BIMI is actively adopted by Verizon (Yahoo !, AOL) and will be implemented in the coming months by Gmail and Microsoft.


SPF is the e-mail authentication protocol based on the origin IP. SPF is a DNS record of the sending domain and contains the reference to all the IPs that are enabled to send e-mails. If the e-mail receiving service recognizes the IP as valid, the e-mail is forwarded to the recipient’s inbox. Otherwise, the communication is labeled as spam. In a nutshell, it certifies that a specific IP is really authorized to send e-mails and there has not been an inappropriate use. The SPF record is validated on the envelope from domain and not on the domain visible to the final customer.

DKIM signature is instead a cryptographic signature that guarantees the integrity of the message from the moment it is sent till the inbox. Brands can sign their e-mails with their domain name and guarantee the integrity of the content of the message. For example in Send, the default DKIM is This ensures that all e-mails sent via Send are properly signed with a domain that has a good reputation.

SPF and DKIM are fundamental requirements to legitimize the sender domain but they may not be enough and sometimes can be subject to false positives. In some cases, the SPF and DKIM checks could highlight problems even in totally legitimate contexts. Think about when an e-mail is forwarded or conveyed through a maling list.

What happens in these cases? When the SPF or DKIM check fails, the receiver mailbox provider – MBP has the right to decide whether the message is legitimate and therefore harmless, or potentially harmful to the mailbox user.

And this is where DMARC – Domain Based Message Authentication, Reporting and Conformance comes into play, a protocol providing brand with the option to indicate to the mailbox provider how to distinguish false positives from spoofing and phishing threats and what actions to take in each possible scenario.

How DMARC works

DMARC is a notification system thanks to which the brand acquires visibility on the traffic of its domain. In fact, in addition to reporting the result of the check on SPF and DKIM, this method creates a link between the domain visible to the reader (header FROM – RFC 5322) and the technical domains (Envelope From domain RFC 5321 and DKIM domain).

If the visible domain – from – is the same as the SPF or DKIM domain, then the DMARC Alignment occurs and the e-mail is delivered correctly.


DKIMFig. 1: Contactlab applies a DKIM linked to the domain to its service e-mails


In the event that DMARC detects a misalignment between the domains, it is the brand that indicates to the mailbox provider receiver such as Gmail, Microsoft, Yahoo! …, how to manage the non-aligned e-mail. And it does it using a progressive severity logic which requires the MBP to:

  • p=none → do not apply any policies and do not take any actions with the e-mail in error
  • p=quarantine → mark the non-aligned e-mail as spam
  • p=reject → reject the e-mail

Note that the above policies also influence BIMI, in particular the requirements to activate it are:

  • Quarantine DMARC policy or reject.
  • DNS BIMI records and compatible logo.
  • Good domain reputation.

It appears immediate that with the spread of DMARC, the customization of the DKIM domain and its alignment with the sender’s domain or subdomain is increasingly required.

Said that, what does Send offer?

Send provides the tools to achieve full compliance with the DMARC requirements and enables you to take advantage of the benefits offered by its adoption.

In particular, it is possible to manage customized DKIMs on a domain basis within a single Send account, ensuring for each domain the alignment with the brand’s sending domains.

In this way, the brand can use different domains for different newsletters (product mailings, commercial communications, etc.), always comply with DMARC and ensure the highest level of deliverability.

To find out the requirements for multi-DKIM activation, contact Contactlab representative or our Customer Service. In addition, the Contactlab Deliverability Team is available to help you in the correct implementation of the DMARC policy, with technical and strategic suggestions.

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Spam filters, spam words and how to test before delivery – Part 3

The problem of spam is very common and one of the biggest nightmares for communicators. However, there are many anti-spam techniques. This article focuses on content-based spam filters, as they can be useful when creating emails and help prevent potential filtering problems.

Spam filters: The environment

Many spam filters use message content analysis to determine whether the email design, content or certain visuals could be the source of undesirable messages.

Two of the most popular content-based spam filters are SpamAssassin and Cloudmark. They are automatically used by many email providers and employ complementary approaches. As a result, it is useful to know both.


  • SpamAssassin

Uses a wide variety of techniques to eradicate spam messages from an inbox. One of these is a rule combination that looks for suspicious content and other spam indicators.
The process is based on the analysis of all received messages and the assignment of a total score, according to individual characteristics.
All messages with a score equal to or higher than 5 are generally regarded as spam. But as it is free and open software, every installation can be highly customized by, for example, making the filtering process more relaxed (by increasing the limit beyond 5) or more aggressive (by setting the score lower than 5).

You can verify the SpamAssassin score directly in Send, through the email creation tool.

  • Cloudmark

Cloudmark Inc. is a private company whose software protects against spam, viruses, phishing and other email and mobile messaging threats. The service is active for more than a billion customers of the biggest ISPs in the world, protecting 12% of global email accounts.
Cloudmark uses the inbox network of the ISP where it is installed, to create fingerprints of spam emails and define, as a result, the characteristics of similar messages, through a constant update process.To explain how Cloudmark works in simple terms, it could be said that it divides emails into distinct sections (header, body, footer, text, images, and so on) and then ‘learns and memorizes’ all the recurring elements of spam mails as characteristics of inappropriate messages, based on user reports.As a result, a message that wasn’t initially regarded as spam by Cloudmark, may later be filtered out if, for example, the particular campaign has been delivered using inappropriate contact lists.


The Contactlab Deliverability Team (link con ancora giusto has tools that can verify Cloudmark filters.

 How to reduce the risk of spam filters reacting to an email’s content 

  •  Clean HTML code

As with every language, HTML code has its own grammar rules, vocabulary and syntax. An HTML-based communication that breaks certain rules or includes typos can, as a result, be sent straight to the spam folder. For this reason, there are ‘validation’ processes that check whether a communication follows the rules. is one example of where you can check the quality of your HTML.

But unfortunately, validation can be a substantial challenge! In fact, it often results in a false-positive and, because if this, it would be almost impossible to completely validate a ‘modern’ email. However, we still recommend checking the test results, to have an indication of potential coding errors.


  • A strong balance between images and text

Your goal should be to have a strong balance between text and images, according to what is appropriate for your business.
Use some text in the email body, to ensure your communication is clear, even if the images are not shown.

In addition, pay attention to the overall message size, and try not to exceed 20kb. The use of large images without text can alert spam filters. Historically, spammers used big images instead of text, so programs could not read the content.

  • Do not use URL shorteners

We recommend that you use shortening tools such as Bitly, and so on, as little as possible, because spammers have deployed them a lot to hide their often already blacklisted and dangerous links. As a result, some anti-Spam filters have blacklisted the URL shortener domains, and their use can result in your emails being sent straight to the spam folder!

  • Avoid using plaintext URL links in text

HTML allows links to be inserted from any text to any URL. As a result, wrongdoers can hide dangerous links under apparently legitimate ones.

For this reason, you should only insert links as either ‘pure’ text or images, and NEVER as addresses in the format. Because link tracking (a very important marketing tool) rewrites your URLs, spam filters can pick up the inconsistency between the displayed link and the one used, then wrongly filter out your genuine emails!

  •  Use a visible unsubscribe opportunity

The ability to unsubscribe should always be present and visible, because if readers cannot easily do so, they will highlight your message as spam and damage your reputation. It preferable to lose a contact rather than being filtered!

  • Alternative text version

Emails can be sent as text, HTML or HTML with alternative text versions. It is good practice to always use an alternative text version to help avoid problems with anti-spam filtering. In fact, an alternative text version is important, as certain apps and email clients do not manage HTML, while some people simply prefer it, and block any HTML emails. However, the text version should be as consistent as possible with the HTML one.
In Send, you can auto-generate a text version by clicking the appropriate button.


  • Spam Words

In the past, some words, known as ‘Spam Words’ were forbidden. They should still not be used if you want to avoid the risk of your emails being regarded as spam. There were also words that spammers bypassed with simple tricks, by writing, for example, the word ‘Viagra’ as ‘V1agra’.Ironically, an otherwise correct email with certain words in the content, could automatically be regarded as spam, while junk mail can be delivered to the inbox, just by disguising the hot words.Fortunately, anti-spam filters have evolved, and it is difficult for just a single word to result in a message being sent to the spam folder.

And, while it is still important nowadays to avoid text that could be considered as spam, this is not enough! Modern anti-spam systems use Bayesian filters to assess an email’s value, directly from a reader’s behavior.

Bayesian filters apply the Bayes theorem to email analysis, by which every event that has a probability can be valued according to events that have already taken place. In the case of anti-spam analysis, if an ‘N’ number of previously analyzed emails have been marked as spam by a reader, and they all contain a particular word, the filter deducts that the presence of the same term in the next email increases the probability it will also be spam.

In particular, you should:

  • Think of emails that increase interaction.
  • Test emails before the delivery.
  • Monitor your performance according to email domains.
  • Follow content best practice.

But, above all, you should use common sense when making any decisions about email copy and design. Put yourself in the recipient’s shoes and decide whether the message would be well received or regarded as undesirable.

And if you need professional help, feel free to get in touch with the Contactlab Delivery Team.

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Trend for recipient domains: A tool that monitors the receipt of emails – Part 2

Following on from the discussion about emails without reachable addresses, this series of articles about deliverability continues. Now, we move on to investigate recipient domains and their behavior when emails are delivered.

What are the benefits of the Trend for recipient domains tool?  

 The powerful Trend for recipient domains tool is available to all Contactsend users. This reporting tool enables an extended analysis of performance trends over time – opens, bounces, unsubscribe events and similar –  arranged by each monitored domain.

Why is this kind of analysis important?
To successfully evaluate deliverability, it is essential that you identify and highlight anti-spam filtering events, or any drop off in performance related to specific recipient domains.

In general, a deliverability problem usually relates to a single mailbox provider. That is, a single domain or a group of domains. It rarely involves all the recipients.

Unfortunately, if you carry out a general performance analysis, potential problems may not be identified. The open and bounce data needs to be looked at in terms of individual domains, to see the data fluctuations over time for each domain. Possible anomalies are highlighted as a result, and this Contactsend tool demonstrates its real value.

The Trend for recipient domains tool enables you to determine the parameters that you want to analyze, together with the appropriate domains, which you can select from the top 100 that you have contacted the most in the past. The output is a dashboard, which displays key reputation-focused metrics.

The same page may also include an Inbox Placement analysis, which is based on a predefined number of deliveries that are selected at random through collaboration with Return Path.

To find out more about Special Reports, see the Contactsend Guide.

Why should you analyze your email delivery performance?

The analysis enables you to identify abnormal results that may have a critical impact on delivery performance.

It is generally useful to monitor the delivery rates for your top 10 domains. This is because they represent, on average, 80% of all deliveries and, as a result, provide a comprehensive and relevant basis for data analysis. Conversely, if you keep track of too many domains, the final dashboard would be unreadable.

Further, it is vital that email delivery process flows are coherent, to eliminate possible analysis anomalies. For example, a company could be subject to divergent flow attributes and characteristics linked to different destination countries, or types of message.

Contactsend enables any potential bias to be managed and reduced, by differentiating email flows through email groups. The Trend for recipient domain report can be focused on one email group at a time, and it is recommended that groups are organized in the most consistent way possible.

The importance of being informed about emails with no reachable addressees: Bounces

A bounce is an automatic message the sender receives when they try to deliver an email that is not accepted by the recipient server. The bounce message includes the reason why it happened. By analyzing bounces, you can understand the origin of certain potentially critical issues and, as a result, intervene in a timely fashion.

Bounce data includes both quantity and quality aspects related to the type of bounce, the domains they occur on and so on. It is important not to underestimate these two aspects, to be able to gain the most comprehensive overview.

To learn more about bounces, see this article.

The open rate trend analysis as a measurement of anti-spam filtering

The open rate trend analysis can be one of the most representative assessments of anti-spam filtering. Comparing the open rate trend for individual domains is essential when identifying these critical issues.

Normally, all the main domain trends result in a consistent and comparative performance over a defined time frame. Some mailbox providers will always be a little bit under the average values recorded for all the domain groups, while others will be higher.

These small differences are mainly the result of the inherent differences between providers. For example, some clients automatically download images, including the tracking pixel that notifies about the opening of an email. This results in a slightly higher open rate. Other providers may return lower open rates because the mailboxes are used as secondary accounts, or their owners do not fully understand how to use them. But usually, the domains will all show roughly the same performance when they are compared with each other under normal conditions.

However, when anti-spam filtering is being applied, you will often see a sudden decrease in the open rate for a specific domain or provider – if emails don’t reach the inbox, recipients cannot open them. When this happens, the open rate is extremely valuable. You can watch for significant performance differences over time for the relevant domains and, as a result, use this information as a filter value.

Using the Trend for recipient domains report

To use the report, do the following:

  1. Sign in to the platform and click Analyse > Trend for recipient domains.
    The appropriate Special Report page displays with sample settings.
  2. Under Top 100 domains control panel, select your required parameters:
    1. Click the metric that you want to measure.
      For example, Bounce.
    2. Click the required period to generate the appropriate view.
      For example, 3 or 6 months. 3M is selected by default.
    3. Click the appropriate group.
      The best compromise is weekly.
    4. For domains, click detailed.
    5. Select the appropriate email group.

  1. Under Monitored domains, select the ones that you want to compare.
  2. When you are finished, click Process reputation metrics.
    The appropriate trend calculations display.

 If you are a new Contactsend user, or you have not yet used the Trend for recipient domains tool, we suggest that you start by following the steps described in this article to become more familiar with its use. You can then explore all the available options to customize your analysis as required.

To maximize message delivery and receipt, it is very important that you pay close attention to deliverability. For this reason, the next deliverability article will focus on anti-spam filters and their application.

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The magical world of bounces: Emails with no reachable addresses – 1st Episode

Without doubt, the communications bounce rate has become increasingly important to companies in recent times. But few realize, however, that there is a rich, varied and valuable world of information and recommendations behind the word bounce, which even today, is undervalued.

At Contactlab, we have always been deeply involved in this topic and now, we would like to share what we have learned with you, through a series of articles about deliverability. Let’s begin with a definition of a bounce message, then continue by highlighting the value that can result from their analysis.

What is a bounce message?

A bounce message is automatically sent to the originator of an email when it is not accepted by the receiving server. It includes the reason why the email has been bounced. Everyone that sends emails has received one of them, at least once in their online life.

So, what actually happens? When an email is sent, a dialogue is established between the sending and receiving servers. In general, this takes place through SMTP, a collection of rules and convention models that are used to exchange messages.

Unfortunately, the two servers cannot always establish a relationship, and for this reason, bounce messages are created. Depending upon when they are created, bounces can be subdivided into two types. Synchronous messages are sent during the SMTP conversation, while asynchronous ones are sent at other times.

What are the reasons why bounce messages are generated?

There are many reasons. They can be the result of, for example, a nonexistent address, a full inbox, the message being regarded as spam, a poor sender reputation and so on.

There is a three-number code within the bounce message that represents the reason, according to accepted conventions. As a result, the sender can see why the message has not been delivered and attempt to resolve the problem. The code always begins with a 4 or a 5, and is written as 4xx, 5xx, 4.x.x. or 5.x.x.

The code is often followed by text that is intended to clarify the bounce reason. However, despite standards and conventions, every receiving server is independently configured with a certain degree of SMTP message management flexibility. This translates into a large variety of bounce messages, because of the diverse ways in which the same message is communicated by different providers.

The smaller providers, as well as the wide range of company domains, make the situation even more difficult. Completely different and generic messages are delivered, resulting in a lack of clarity and text that can easily be misunderstood.

All providers of professional email delivery tools must be able to correctly collect, understand, analyze and categorize the wide range of bounce messages.

In doing so, Contactlab has defined precise classification rules, resulting in 24 bounce categories. This data is readily available in Contactsend reports and the Trend for Recipient Domains analysis.

How can a bounce be classified?

Bounces are generally categorized as either hard or soft.

Hard bounces are perpetual errors that happen because the contact address is permanently unavailable. Since these errors cannot be resolved, the relevant address/addresses must be removed/deactivated. According to certain best practices, the deactivation must take place after one or two bounce episodes. Hard bounces are always identified with a 5xx code.

Soft bounces are temporary errors that happen because although the address is theoretically active, it is not available at the moment. They can occur, for example, if the inbox is full, or when the relevant software is currently not responding. In the case of soft bounces, the address/addresses should not automatically be deactivated. They will only be removed in the event of prolonged inactivity. Because of the wide range of soft bounce types, there are differences in how they are managed.

Delivery Time Expired is a particular type of soft bounce. A sending system tries to contact the receiving server. If it does not answer, the sending system will periodically try to contact the receiving server again, before eventually giving up.

In this instance, Contactlab tries to deliver the message for 48 hours. If, after this time the receiving server has not answered, a Delivery Time Expired bounce is generated. These bounces, however, do not result in the relevant email address being removed from a list.

The receiving server may not answer for two reasons:

  1. The server itself does not exist. A case can be when the email address includes a nonexistent domain.
  2. The server does not want to answer the sender any more. This can happen if, for example, the server has received too many emails from that sender, or it believes the sender delivers spam messages.

Soft bounces are usually identified with a 4xx code, but they can also have a 5xx one.

Why is it important to monitor bounces?

It is important to be able to recognize bounces because correct management enables the problem to be identified quickly, and potentially be resolved. The following key factors can be linked to bounce messages:

  • The quality of the message content
  • The quality of the contact list
  • The reputation of the sender IP
  • Sending behavior or frequency

For all these aspects, certain bounce types are more relevant than others.

For example, Hard Bounce and Delivery Time Expired are the most important bounces when considering list quality. Reputation is one of the most relevant bounces for sender IP reputation, together with perhaps the content detail of a Delivery Time Expired message, as well as Spam Content and so on.

Bounce Rate, which is calculated by comparing the number of bounces with the quantity of sent emails, is a common metric that helps us understand deliverability. Bounce rate analysis can be particularly helpful when identifying substantial or extended problems. But to be able to understand some issues, they need a deeper analysis, for example, by differentiating between the kind of bounce and the domain/s involved. A bounce rate of 3% is generally not a problem, but what if all the bounces are reputation-related? Or what if some domains have a 100% bounce rate?

Contactsend includes a powerful tool known as Trend for Recipient Domains, which provides a broad view of the available information. It allows, for example, an analysis of performance parameters such as openings, bounces, clicks and similar, which are then ordered by time, type and domains. The analysis of bounces enables us to understand the origin of certain problems and then be able to react.

Bounce data is important from both a quantitative and a qualitative viewpoint. How many bounces? What kind of bounce? Which domains are involved? It is key that the analysis of all these aspects and the overall deliverability data should be as comprehensive and complete as possible.

For this reason we are going to see together, in the next Episode, how to analyse trends for recipient domains, both from a qualitative and quantitative point of view, problems that can be registered and how to solve them.

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