How do I troubleshoot emails that are being marked as spam?

We recommend two things:

1) First, check the email headers of one of the messages. The spam filter adds information on why the message was triggered as SPAM. If you don’t know how to read this, feel free to open a support ticket with a copy of the headers.

To check the email headers:

  • Webmail: Open message, then More > Show source.
  • Mail.app: Open message, then View > Message > All Headers.
  • Mozilla Thunderbird: Open message, then View > Message Source.
  • Outlook: Open message, then on the Message tab, in the Options group, click the Dialog Box Laucher. In the Message Options dialog box, the headers appear in the Internet headers box.

An example of headers containing a spam report:

As you can see, there is a series of specific rules that at the end are summed up to have the spam score value. There is a public list of all SpamAssassin rules.

2) Try increasing the score of the spam filter. This can be done in the control panel under the settings of the email account. A low number means a more strict filter and a higher number means the filter is more relaxed. By default we set it to 5.

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