Troubleshooting Outbound Email Issues with YunoHost on AWS EC2: Unable to Send via Nextcloud Mail App

[codelasak]

My YunoHost server

Hardware: VPC bought online AWS EC2
YunoHost version: 11.2.20.2 (stable)
I have access to my server : Through SSH
Are you in a special context or did you perform some particular tweaking on your YunoHost instance ? : no
If yes, please explain:

Description of my issue

I am attempting to set up email services on my YunoHost instance hosted on an AWS EC2. I am using the mail app via Nextcloud. While I can receive emails, I am unable to send emails. I have tested my setup with mail-tester.com.

Here are the steps I have taken so far:

1. DNS Configuration: Configured my DNS records (MX, SPF, DKIM, DMARC) according to the YunoHost documentation.
2. Email Client Configuration: Set up the email client via the Nextcloud mail app.
3. Firewall Rules: Ensured that the necessary ports (25, 465, 587) are open on the AWS EC2 security group.

Issues Encountered:

1. Sending Emails: Emails sent from my YunoHost server via the Nextcloud mail app are not being delivered. Instead, I receive error messages indicating issues with the mail server configuration.
2. Testing with mail-tester.com: The service indicates that emails are not being successfully sent from my YunoHost instance.

[rungeard]

What says the YH diagnosis in webadmin ?

[codelasak]

thanks for help @rungeard

I use AWS SES to SMTP Relay but it does not work. I tested AWS SES with SMTP Test Tool successfully.

When I add SES to Yunohost it doesnt work.

[rungeard]

@codelasak

When I add SES to Yunohost it doesnt work.

What is the error message ?

[codelasak]

I dont get any error mesaage. When I tested with nextcloud it doesnot send email.

[codelasak]

I solved
I used AWS SES in sandbox mode. I must use in production mode.