Support center

Emails from System One end up in SPAM folders

It can happen that emails from System One end up in spam folders. We've taken a number of measures to make sure that this happens as little as possible.

How do spam filters work?

A filtering solution applied to the email system uses a set of protocols to determine which of your incoming messages are spam and which are not. There are several different types of spam filters available:

  • Content filters – review the content within a message to determine if it is spam or not
  • Header filters – review the email header in search of falsified information
  • General blacklist filters – stop all emails that come from a blacklisted file of known spammers
  • Rules-based filters – use user-defined criteria – such as specific senders or specific wording in the subject line or body – to block spam
  • Permission filters – require anyone sending a message to be pre-approved by the recipient
  • Challenge-response filters – require anyone sending a message to enter a code in order to gain permission to send email

Spam filtering solutions are commonly deployed in 2 ways: hosted / “cloud” or as software installed on the users' computers that integrate with an email client such as Microsoft Outlook.


What do we do to avoid being marked as SPAM?

We take a number of measures to make sure that emails sent from System One don't end up in SPAM folders.

  • Quality email server: All the email sent from System One is sent through a premium email delivery service (SendGrid.com). This is important, because they have a good online reputation and aren't blacklisted by  spam solutions. Next to that, they make sure the emails that are being sent have all the correct headers. 
  • Correct configuration: We have configured our DNS records to meet SPF and DKIM requirements.

What can you do to avoid being marked as SPAM?

  • Don't send bulk email: When you want to send an email to a large group of people, System One might not the right solution. Have a look at Mailchimp for instance.
  • Avoid certain words/phrases: Content filters might be triggered by words or phrases very common to spam emails.
  • Avoid overly rich footers: When you have a lot of images in the signature of your email, the email might be classified as a newsletter.

What if your email ends up in a SPAM folder?

There are many different spam filtering solutions, configured by many different system administrators who can all make up their own filter rules. It will happen that your email ends up sometimes in a spam folder.

If this consistently happens with a specific recipient, please ask them to check with their system administrator what is the reason this happens.

We are happy to receive a report from their system administrator, if they believe there is something that we can improve!