Mail doesn't arrive

Step 1

Please check the following details about the mails:

  • dkim
  • spf
  • dmarc

These 3 properties should pass. Our DMARC rule dictates that if DKIM or SPF fails the mail should be rejected by the receivers mail server. This ensures that any fake email would not be delivered to the recipient at all.


ARC-Authentication-Results: i=1;;
       dkim=pass header.s=s1 header.b=H7z0S2Fk;
       spf=pass ( domain of bounces+17379045-1005- designates as permitted sender) smtp.mailfrom="";
       dmarc=pass (p=REJECT sp=REJECT dis=NONE)

There is a Return-Path field in the header of the email, which could look like something as follows:

Return-Path: <bounces+17379045-1005->

This ensures that if the recipient bounces back the email, this information is logged and we can get notified about it.

This field is different from the sender address, which is

Step 2

Since we are using always the same IP ( ), if that is possible, whitelist the emails by IP.