Spam issue

Being caught by the spam filter is killing any e-mail marketing campaign.

These are only some advices and in most cases you won't have any issues with the spam filter even if you don't follow them. But in case of you are caught by the spam filter we recommend you to have a look at this article!

Don't spam!

If you use AcyMailing to send Spam e-mails, you will obviously be considered as a spammer. If your Newsletter is not appreciated by your receivers, you will be considered as a spammer.

Do never buy a list of e-mails form a third party, they are full of non-valid e-mail address and your campaign will be quickly considered as spam. The good point is that you won't interfere with other users using AcyMailing for their campaign. Each AcyMailing installation is completely independent and your spam score depends only on your own server and e-mail.

Optimize your content...

Add more text than HTML tags

Finding a good balance between your real content and your html tags is really the most important point to don't get flagged as a spammer.

Your real content should represent the main part of your e-mail.

If you add a lot of HTML tags everywhere (tr,td,table,div,p,span...) and you almost don't have any text, your spam score will be increased.

Nevertheless the opposite is also true, if you add only text with some links and don't add any html tags, your spam score will be increased as well.

You should find the good compromise between real content and html tags to don't get caught by the spam filter.

So if you're testing your Newsletter template without real content inside, you have high probability to receive your tests in your junk folder, please make sure you're testing your real Newsletter and not only your template.

Don't use "spam words"

Make sure you don't insert spam words in your e-mail such as "free", "sex", "pharmacy"... Those words usually increase a lot your spam score.

Don't S P A C E out your words, don't put strange letters or characters into your emails.

Configure or remove the statistics

In order to handle statistics, AcyMailing adds in each e-mail a small blank picture. That way AcyMailing will know who opened your e-mail and when. But this statistic picture may increase your spam score, especially if the text {Disarmed} is added to your subject each time you send an e-mail. If you disable the plugin AcyMailing : Statistics Plugin, the picture won't be added any more.

This is definitely not required to not be caught by the spam filter but it might help if you have serious spam issues.

You can also configure your AcyMailing : Statistics Plugin to use your own picture and not a blank one.

On all our commercial versions, AcyMailing automatically tracks your links so you can know who clicked on which link in your Newsletter. This system may also increase your spam score so if you have serious spam issues, you should also turn OFF the plugin AcyMailing : Handle click tracking.

Improve your server configuration...

Spread your send process

Sending 10 000 e-mails in few minutes is not a good idea at all and even if your server is configured properly and your e-mail has a low spam score, you will still be considered as a spammer.

You should spread your send process if you have many e-mails to deliver (for example, send 300 e-mails every 15 minutes).

Configure your send process.

Make sure your server is not blacklisted

If your server is blacklisted, your e-mail will be considered as a spam e-mail. You can make sure your server is not blacklisted on this website :

If you're server is blacklisted, you have two possibilities :

  • Fix it! (usually it's a problem of reverse DNS)

  • Use an external SMTP Server so your e-mails are not sent from your own server any more.

Make sure your reverse DNS is configured properly

What's the reverse DNS?

The DNS enables to locate your server using a domain name : Domain name -> Server IP A reverse DNS is the opposite. Using your server IP, the reverse DNS should return your domain name : Server IP -> Domain name

If both entries match each other, we call it FCrDNS ( forward-confirmed reverse DNS or full-circle reverse DNS ).

Some spam filters check that both entries match and if not, your spam score will be increased.

Where should I configure my reverse DNS?

This should be done on your own server, it's not related to AcyMailing. Please contact your provider for more information.

How can I test my reverse DNS?

You can enter your website IP at . Your domain name should appear. (You can use the command line nslookup too)

For example, if we ping, we get the Server IP The reverse DNS of returns so everything is configured properly.

Configure your SPF and Sender ID records

  • What's the SPF (Sender Policy Framework) ? Basically it's a verification on the bounce e-mail address used... It will extract the domain name attached to your bounce e-mail address and make sure that the IP used to deliver the message is allowed to do so by your domain.

  • To configure your SPF, you should generate your SPF record with the help of the openspf website and then include this record at the end of your DNS BIND.

  • The sender-id is the exact same thing except it's done on the from e-mail address used and not the bounce e-mail address.

Improve your message structure...

Configure your sender information properly

We recommend you to make sure the sender e-mail belongs to the same domain as your bounce back e-mail address. They can be different but they should belong to the same domain name.

On, we use the sender : This email address is being protected from spambots. You need JavaScript enabled to view it. and the bounce back e-mail address : This email address is being protected from spambots. You need JavaScript enabled to view it. That way we can handle the bounces on an independent mailbox and not increase our spam score.

Do never remove your default reply-to address!! Even if you don't want reply from your customers, specify something like This email address is being protected from spambots. You need JavaScript enabled to view it. but don't remove it otherwise you will be flagged as a spammer.

Test your spam score

All our paid versions include a spam filter test so you can easily test your Newsletters.

You can also test your Newsletter via or using this free service:

Send a test of your Newsletter to: This email address is being protected from spambots. You need JavaScript enabled to view it. and you will get a message (sent to the e-mail address you specified as "reply to address") including the spam report of your Newsletter:

  • SPF check: Is your SPF valid? We highly recommend you to make sure it is! This verification is done on the domain name used in your bounced back e-mail address.

  • DomainKeys check: this verification is basically the old version of DKIM. Acy does not add DomainKeys on your message, you should see "neutral" here which means there is no positive or negative effect. Your hosting company may validate it... but it's definitely not mandatory.

  • DKIM check: All commercial versions of AcyMailing enables you to sign your message with DKIM. Your hosting company may also enable you to automatically sign all messages sent with DKIM.

  • Sender-ID: Is your sender-id valid? We highly recommend you to make sure it is! This verification is done on the domain name used in your from e-mail address.

  • SpamAssassin check: ham means that your e-mail should not be considered as a spam by SpamAssassin but please also make sure that your SpamAssassin score is as low as possible, your SpamAssassin score should even be negative!

    • The first line indicates your spam score: Result: ham (-4.6 points, 5.0 required) It means our score is -4.6 so the message is not considered as spam as it requires at least 5.0 to be considered as spam.

    • Bayes spam probability should not be superior to 20%

Last updated