Email AWS SES test yields Transaction failed: Nested group

Emails are not going out through (what I thought) was a successful AWS SES setup.

Because this is a new server on Hetzner, no emails via ports 25 and 465 go out until I get/pay my first bill. ;-/
https://docs.hetzner.com/cloud/servers/faq/#why-can-i-not-send-any-mails-from-my-server

Portion of custom_config.ini:

Code (Text):

EMAILNOTIFY_SES='y'
EMAILNOTIFY_SES_FROM_EMAIL='verified@aws.ses'
EMAILNOTIFY_SES_TO_EMAIL='me@me.com'
EMAILNOTIFY_SES_SMTP_USERNAME='XXXXXXXXXXXXXXXXXXXXXXXX'
EMAILNOTIFY_SES_SMTP_PASSWORD='XXXXXXXXXXXXXXXXXXXXX'
EMAILNOTIFY_SES_SMTP_SERVER='email-smtp.us-west-2.amazonaws.com'
EMAILNOTIFY_SES_SMTP_PORT='587'

Here's the output of "emailnotify send testnote subjectnote"

Code (Text):

CONNECTION ESTABLISHED
Protocol version: TLSv1.3
Ciphersuite: TLS_AES_256_GCM_SHA384
Peer certificate: CN = email-smtp.us-west-2.amazonaws.com
Hash used: SHA256
Signature type: RSA-PSS
Verification: OK
Server Temp Key: ECDH, prime256v1, 256 bits
250 Ok
250-email-smtp.amazonaws.com
250-8BITMIME
250-STARTTLS
250-AUTH PLAIN LOGIN
250 Ok
334 VXNlcm5hbWU6
334 UGFzc3dvcmQ6
235 Authentication successful.
250 Ok
250 Ok
354 End data with <CR><LF>.<CR><LF>
554 Transaction failed: Nested group
451 4.4.2 Timeout waiting for data from client.

---

I know that the "Timeout waiting for data from client." is normal, but I don't know what to make of the "Transaction failed: Nested group" message.

Has anyone run into this before?

If there's no obvious solution, how can I setup postfix to start sending out via port 587 instead of the port 25 default?

• CentOS Version: AlmaLinux 9
• Centmin Mod Version Installed:140.00beta01.b125

 

Thanks... I'll give it a shot.

 

No such luck. I'm going to give up on it and just rely on using AWS SES within postfix main.cf & sasl_passwd.

Just so you know, this link doesn't have any immediately actionable info. You may want to change up to another link like How to configure Amazon SES with Postfix or similar.