SMTP error from remote mail server after end of data

theara ki

Jan 29, 2019
Phnom penh Cambodia
cPanel Access Level
Website Owner
Dear all,
please hlep me, i just setup new WHM&Cpanel for testing, but i try send email test to gmail, it's reply error with this message in mail log :

1gof6H-0002m5-Tv ** ki***** R=dkim_lookuphost T=dkim_remote_smtp []: SMTP error from remote mail server after end of data: 550 Requested action not taken: mailbox unavailable

I user my local mail server in private IP and make share ip with public IP and Nat from Firebox watchgaurd, so i'm not experience with this. i'm not make sure i wrong configure with firebox or what.


Technical Support Community Manager
Staff member
Nov 14, 2017
Hi @theara ki

While we're unable to provide support for your networking configuration, that error is received typically when the mailbox you're sending to doesn't exist on the server or can't receive mail. Are you sure that the address you're sending to exists? Furthermore what are the DNS resolvers set to in /etc/resolv.conf?