could you please explain me what is this error?
which side is the problem?
-------- Mensaje original --------
Asunto: Returned mail: see transcript for details
Fecha: Wed, 7 Sep 2011 23:50:41 GMT
De: Mail Delivery Subsystem <MAILER-DAEMON@imbhub-ru15.nam.nsroot.net>
The original message was received at Wed, 7 Sep 2011 23:49:32 GMT
from imbdmz-ru09.namdmz.dmzroot.net [172.27.201.13]
# d: error-header.nohash,v 1.1 2003/12/11 09:32:08 as82064 Exp
This an automated message from the E-mail System at Citigroup.
We had a problem trying to deliver the mail you sent.
If you do not understand the error message below, or
need assistance diagnosing the problem, please contact your
local technology support or Helpdesk area.
If you believe the problem is on the Citigroup email system, please
contact the recipient at Citigroup by other means and request that they
open a trouble call with their Helpdesk.
----- The following addresses had permanent fatal errors -----
(reason: 530 5.7.1 Client was not authenticated)
----- Transcript of session follows -----
451 4.4.1 reply: read error from [10.213.193.19]
... while talking to [10.203.137.44]:
>>> MAIL From:<firstname.lastname@example.org> SIZE=31787
<<< 530 5.7.1 Client was not authenticated
554 5.0.0 Service unavailable