I can send emails but I can't receive them

benlyazid

Hi, I hope this message finds you well. I recently deployed Mailcow on an AWS server, and I’m encountering an issue where I’m unable to receive emails from Gmail. When attempting to send emails to Gmail, I receive the following error message:
**The recipient server did not accept our requests to connect. Learn more at https://support.google.com/mail/answer/7720 [mail.my-domain.ma. ...*: timed out]

Upon investigation, I suspect that the problem may be related to the PTR record, as the DNS records page currently displays:
ec2----*.eu-west-3.compute.amazonaws.com** instead of the expected: mail.my-domain.ma

I’ve tried adding PTR records in AWS Route 53, but unfortunately, it seems to have had no effect. I’ve been grappling with this issue for over two weeks now, and any assistance from the community would be greatly appreciated.
If anyone has insights or solutions, please share them. Your help will be invaluable in resolving this challenge.
Thank you in advance!

esackbauer

You do it with EC2, not with Route 53:
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/elastic-ip-addresses-eip.html#Using_Elastic_Addressing_Reverse_DNS

benlyazid

esackbauer
Thank you so much for your assistance. I’ve corrected the PTR record value. However, I’m still unable to receive emails. Could it be a matter of waiting for some time for the changes to take effect, or is there a possibility of another underlying issue? Your continued help is greatly appreciated. Once again, thank you for your support.

esackbauer

make sure your firewalls on EC2 are open for port 25. Check if you can telnet into postfix from another public IP.

benlyazid

esackbauer
Do I need to open port 25 even if I am using Sendgrid as an SMTP relay?

esackbauer

On which port do you think you will receive mails??
Please stick to the documentation:
https://docs.mailcow.email/getstarted/prerequisite-system/#firewall-ports

benlyazid

esackbauer
Thank you so much. The issue you pointed out is that I need to open the port. I initially believed that using SendGrid as a relay would negate the need for it. I appreciate your guidance once again. 😇

esackbauer

benlyazid I initially believed that using SendGrid as a relay would negate the need for it.

You should educate yourself about SMTP, you need to have a proper understanding otherwise you will not be able to run a mail server successfully. Youtube provides lot of explanatory videos on that.

benlyazid

esackbauer
Thank you for the suggestion. I look into educating myself further on SMTP. Your guidance is appreciated, and I’ll explore the resources on YouTube to enhance my understanding.