550 Sender verify failed (following server migration)


Apr 6, 2015
cPanel Access Level
Website Owner
Hi to the CPanel community,

I browsed a number of threads here about 550 error but I have yet to find a solution and hope one of you will be able to help.

For starters:
I manage a Joomla website (- Removed -), Cpanel is installed on the server (but not WHM).

Before server migration, I was sending monthly newsletters with ACYmailing (version is 4.5.1)

Following migration a couple weeks ago, I started having issues:
About 90% of the recipients give me the 550 error.

What is strange is that we have another website (- Removed -) on the same server and when I send the newsletter to my @ domain.com address I get the same error as the 90% of my mailing list.

Here is the error message:
[email protected]
host mail.domain.com [70.38.xx.xx]
SMTP error from remote mail server after RCPT TO:<[email protected]>:
550-Verification failed for <navyreco @ blahblah.privatedns.com>
550-The mail server could not deliver mail to navyreco @ blahblah.privatedns.com. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.
550 Sender verify failed
Something else important mentioning:
I have NO IDEA where this "navyreco @ blahblah.privatedns.com" is from.
(I have hundreds of 550 error message dumping into my webmail address because navyreco @ blahblah.privatedns.com obviously does not exhisit.)

My ACYmailing is setup so that:

From Name = Navy Recognition
From Address = newsletter @ domain.com
Reply-to Name= Navy Recognition
Reply-to Address = newsletter @ domain.com

The only thing I tried to troubleshoot was adding "navyreco @ blahblash.privatedns.com" in my Email Authentication/SPF/Advanced Settings/"Additional Hosts that send mail for your domains"

But it didn't work.

I saw a lot of thread talking about exim file tweak but there is no exim file on my server (is this because I don't have WHM ?)

Any help would be greatly appreciated (in simple terms: as you can probably tell, I am no expert).

- Modified to remove personal details - Infopro -
Last edited by a moderator:


Well-Known Member
May 20, 2003
cPanel Access Level
Root Administrator
I've modified your post to remove any personal details. You really should be more careful on a public forum with specific details, like email addresses and domain names.

Do you have root access to this server and can check your system logs? If not you might want to contact your Hosting Provider about this.