Hello,
I have these messages sent only to a specific domain that aren't being delivered.
This is the error I got from SMA/Message tracking:
19 Jul 2021 18:06:12 (GMT +02:00) SMTP delivery connection (DCID 14832928) opened from Cisco IronPort interface x to IP address x on port 25.
19 Jul 2021 18:06:12 (GMT +02:00) Delivery connection (DCID 14832928) successfully accepted TLS protocol TLSv1.2 cipher DHE-RSA-AES256-GCM-SHA384 None.
19 Jul 2021 18:06:12 (GMT +02:00) (DCID 14832928) Delivery started for message 28415032 to x
19 Jul 2021 18:06:12 (GMT +02:00) (DCID 14832928) Message 28415032 bounce verification rewriting sender x to Unknown.
19 Jul 2021 18:06:12 (GMT +02:00) (DCID 1473574) Message 28415032 to x bounced by destination server. Reason: 5.1.0 - Unknown address error ('550', ['x is not allowed to send mail from Y.net']) [('from', '=x')]
19 Jul 2021 18:06:12 (GMT +02:00) Start message 28415035 on incoming connection (ICID 0).
19 Jul 2021 18:06:12 (GMT +02:00) A new message 28415035 was generated to handle bounce of message 28415032.
Could be this something to do with my ESA configurations or do you think that this is could be only on the recipient side?
Thank you in advance for your support.
Best Regards,
Nuno Inácio
