Cannot send e-mails from any e-mail clients

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9 msg	Mail Rejected when we relay for a client.
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Cannot send e-mails from any e-mail clients
\ Ismet Togay (11 Apr 2007)
. \ Noel Jones (11 Apr 2007)

1 msg	Re: outbound mail failure - need to fix asap -S...
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3 msg	smtpd_auth

Subject:	Cannot send e-mails from any e-mail clients
Group:	Postfix-users
From:	Ismet Togay
Date:	11 Apr 2007

Hello,

This is my first message to the list! Nice to meet you :)

I have a problem about Postfix:

I manage my VPS using the Webmin control panel. I installed Postfix and
Dovecot IMAP/POP3 Server. Everthing seems to be working fine. I can send and
receive e-mails using the webmin. I can also receive the e-mails from an
e-mail client, like Outlook Express. But the problem is, "I cannot send
e-mails from any e-mail clients".

For instance, the error message Outlook Express gives is the following:
"The message could not be sent because one of the recipients was rejected by
the server. The rejected e-mail address was 'ismet'. Subject
'qweasd', Account: 'mail.mydomain2.net', Server: 'mail.mydomain2.net',
Protocol: SMTP, Server Response: '554 5.7.1 <ismet>: Relay
access denied', Port: 26, Secure(SSL): No, Server Error: 554, Error Number:
0x800CCC79"

I have searched for this error on the Internet. Most of the suggestions are
about checking/enabling "My server requires authentication" option in the
outgoing mail server configuration. But, in my Outlook Express, that option
has been already selected. So, the problem should not be related with that.

My Postfix configuration file is at the end of this message. I am not that
experienced on linux and mail servers. I tried to configure Postfix looking
at the tutorials and manuals on the net. So, can you help me in a
step-by-step approach?

On the other hand, my VPS has two IP addresses, 89.xx.5.180 and 89.xx.5.181.
At the moment, I have two domains: mydomain1.com, mydomain2.net. One of them
is using the first IP, the other is using the second IP. Thus, I do not know
how to configure them properly in Postfix.

If needed, my server configuration is : Debian 4.0 Etch, Apache 2.2.3, Php
5.2.0, MySQL, 5.0.32, BIND 9.3.4, Postfix 2.3.8, Dovecot 1.0, etc..

Any help appreciated!
Ismet Togay

******************POSTFIX - MAIN.CF******************
# See /usr/share/postfix/main.cf.dist for a commented, more complete version

# Debian specific: Specifying a file name will cause the first
# line of that file to be used as the name. The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${queue_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${queue_directory}/smtp_scache

# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.

alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
mydestination = mydomain1.com, mydomain2.net
mailbox_size_limit = 0
recipient_delimiter = +
virtual_alias_maps = hash:/etc/postfix/virtual
virtual_alias_domains = mydomain1.com, mydomain2.net
smtpd_recipient_restrictions =
permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination
mynetworks = 89.xx.5.0/24
******************POSTFIX - MAIN.CF******************