Address not found, 550 5.1.0 Recipient rejected, Google Cloud

clyde01

Registered
Dec 9, 2019
3
1
1
Singapore
cPanel Access Level
Root Administrator
Hi, I have set up a VM instance on Google Cloud Platform (GCP) running CentOS 7.7 with WHM v84.0.16 installed.
I have configured Exim with mailgun and it is able to send emails out via mailgun.

However, I am unable to send email from my Gmail to my DOMAIN email (I am able to receive emails sent out from my DOMAIN email). I encountered the 550 5.1.0 Recipient rejected error message whenever I try to send an email to my DOMAIN email.

I have :
  • acquired my domain name from Namecheap and have configured the nameservers in Cloud DNS (currently using google nameservers)
  • enabled the Public DNS PTR record to my VM instance
  • configured SMTP to use port 2525 instead of port 25 as GCP blocks it
  • ports 465, 587 and 2525 have been allowed on the firewall and I am able to telnet in at port 2525
  • Email Deliverability reports configurations as valid in both WHM and cPanel
  • added MX records to point to mail.mydomain.com
 

cPanelLauren

Product Owner
Staff member
Nov 14, 2017
13,304
1,252
313
Houston
Hello @clyde01

  • When you send mail to yourself from Gmail, is the transaction (or even SMTP connection) logged in the exim log at /var/log/exim_mainlog
  • Is the domain located in /etc/localdomains and not present in /etc/remotedomains ?
  • Is there a CNAME record present for mail.mydomain.com (i.e., does it resolve to an IP address)
  • Does this only occur with Gmail or does it also occur with other email service providers
  • Do you now or have you ever had Google's email suite?
 

clyde01

Registered
Dec 9, 2019
3
1
1
Singapore
cPanel Access Level
Root Administrator
Hello @cPanelLauren,

  • No, there is it a transaction logged in the exim log when I send an email to the DOMAIN email
  • Yes, the domain is located in /etc/localdomains and NOT present in /etc/remotedomains
  • No, there is no CNAME record present for mail.mydomain.com, instead I have an A record resolving mail.mydomain.com to the IP address
  • No, it also occur with other email service providers
  • No, I never had Google's email suite (GSuite)