Thanks for this software. It rocks.
I am getting some mail bounced back. I’ve got all green/ok on the Status page.
DNSEC is configured correctly
This is all good: http://mxtoolbox.com/domain/box.paloaltoimpactcenter.com/
Not on any blacklists I could find
It’s happened with two different recipients with the following error codes…
1): Subject: Undelivered Mail Returned to Sender
Diagnostic-Code: smtp; 554 Denied [CS]
2): Subject: Undelivered Mail Returned to Sender
Diagnostic-Code: smtp; 553 5.3.0 nlpi185 DNSBL:RBL 521< 188.8.131.52
Any ideas what to try next? Everything seems good on my end.