Unable to send eMail from a UNIX-Host ( using mailx ) to a Outlook-email-addres(Win)

Hi

A) I am able to send eMail using mailx from a UNIX ( solaris 8 ) host to my Outlook-email-ID : FName.Surname@Citigroup.com ( This is NOT my actual -eMail-ID). But in Outlook the "From :" eMail address is displayed as
" usr1@unix-host1.unregistered.email.citicorp.com " .i.e the words "unregistered.email" seems like a mystery.

B) But when I try to send eMail from another UNIX host ( which has its User-accounts locally in /etc/passwd and /etc/group - i.e it NOT part of NIS/NIS+ ; but its on the network -> pingable from other UNIX-hosts / Windows hosts ) , I received Failure report , part of which is , given below:

===============
From MAILER-DAEMON Mon Feb 14 15:47:46 2005
Date: Mon, 14 Feb 2005 15:47:46 +0800 (SGT)
From: Mail Delivery Subsystem <MAILER-DAEMON>
Message-Id: <200502140747.j1E7lkS29439@unix-host2.aspac.citicorp.com>
To: usr1
Subject: Returned mail: see transcript for details
Content-Length: 1477

This is a MIME-encapsulated message

--j1E7lkS29439.1108367266/unix-host2.aspac.citicorp.com

The original message was received at Mon, 14 Feb 2005 15:47:46 +0800 (SGT)
from usr1@localhost

----- The following addresses had permanent fatal errors -----
FName.Surname@Citigroup.com
(reason: 550 Host unknown)

----- Transcript of session follows -----
550 5.1.2 FName.Surname@Citigroup.com... Host unknown (Name server: mailhost.aspac.citicorp.com: host not found)
.
.

=============

Pls help to send email from unix-host2 to Outlook-eMail-account. ( ie. section-B above).

thanks in advance!

Regds
Vetri

check for your mailhost entry in the /etc/hosts.
Might be wrong......

Please describe your SMTP architecture.

What MTA are you using? MUA? etc.

If these terms are not familar to you, then I kindly suggest you need to review the basics of SMTP architecture. A Google search on these terms will be very helpful.

SMTP MTA MUA