Why are most emails marked as spam?

Question

What causes most emails to appear in my Suspended tickets view?

Answer

This may be related to the headers of the emails that you forward to Zendesk. The email headers contain unhealthy resources, which email filters use to mark emails as spam.

Factors that may flag customer emails as spam

An email header that contains a domain listed in a public blocklist signals that the domain might be associated with spam or malicious activities

If an IP address in the email header appears in a public blocklist, the IP address likely sent spam or other unwanted content

If you enabled enhanced sender authentication and the sender's email provider doesn't have properly configured DKIM, DKIM, and DMARC authentication

To determine if your emails contain unhealthy resources

Extract the source of the email from the ticket

Download and open the EML file in a text viewer, then review the IP addresses and domains that the email passed through

Check if an IP address or domain is blocklisted. Use an external tool such as MXToolbox. This tool shows if the IP or domain is in any public blocklists. If the IP address or domain is blocklisted, contact the owner and request its removal from the blocklist.

For more detailed information about why emails are detected as spam and how to address this issue, see the article: What does "Detected as spam" mean?