Client not allowed to relay - help required

[paralikar]

Hi,

I installed qmail-toaster 1.03-1.3.15.x86_64 version. The whole installation went fine and the server too is working fine except that we are unable to connect using outlook from outside the network and send emails. We are receiving below error message:
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@4000000049abd5133132b80c CHKUSER accepted sender: from <tom@mydomain.com::> remote <etg91:unknown:203.199.178.229> rcpt <> : sender accepted
@4000000049abd5140debb2a4 CHKUSER rejected relaying: from <tom@mydomain.com::> remote <etg91:unknown:203.199.178.229> rcpt <sample@etisbew.com> : client not allowed to relay
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Issue is same for any domain I want to send using outlook or outlook express.

In outlook, we have enabled "outgoing server required authentication" option. But still this problem persists.

Googled through but any of those given solutions worked.
- Added the network "203.199.178.229" into tcp.smtp and ran the command "qmailctl cdb".
- No firewall issue, as the SMTP is picking up the connection.
- did not see any error related to spamassassin or qmail-scanner.

Can anybody throw some light on what needs to set or changed at server end?? Am I missing anything?