Common Spam Scenarios
You may encounter various spam scenarios when sending an email. We've outlined a few of them and ways to handle them.
To preserve their email sending reputation, some email providers will review all outbound emails through their spam filter before sending. Spam filters work by comparing emails to an extensive list of matching behaviors and giving each behavior a score. If the cumulative score of an outbound email exceeds a set threshold, the email is blocked. Some spam filters look for automated senders like Nylas and add a score for using them because spammers often use similar automated services. This can cause some emails that have a concerning spam score to go over the blocking threshold when sent through Nylas. Please reach out to your email administrator if you have any questions about their spam filters.
We return that the email was blocked for spam in the API response, but we don't have any visibility into exactly what caused the block.
Many Exchange servers have 2 SMTP servers. One is for automated sending from applications like Nylas, and the other is a smaller service that sends emails from the Outlook email client directly.
Since the SMTP server handles the larger sends, it is more likely to get flagged as spam. This is due to the volume spike and bulk sends compared to the individual emails when sending from the Outlook client.
Emails sent through Nylas have to through the larger server and are more likely to get caught in any spam blocks on the server's IP address. If you see a bounce message indicating your IP address has been blocked, bring it to the attention of your email administrator. They can look into solutions such as getting a new IP address for the SMTP server. You should also review your outbound emails and ensure you are following best practices to avoid being blocked.
Bulking refers to email servers' practice of accepting emails sent to their users but routing them to a BULK, SPAM, or JUNK email folder or label. There are various reasons that email providers do this, but Nylas has no visibility or control over that process. Often this happens when a recipient's email server starts to receive large amounts of email from an IP address that never sent it email before. Or when recipients of earlier sends have flagged the emails as junk.
It's important to ramp up sending to new contacts and ask your recipients to mark the email as not spam. You should also respect any unsubscribe requests and remove recipients who are not engaging with your mail.
To avoid any of the scenarios listed, you can read our guide on Improving Email Deliverability.