Sender address rejected: Domain not found (in reply to RCPT

Hi,

if I send emails from thunderbird I have no problem,

if I send emails from roundcube using the same email address (same server) the recipient address reject my emails with this reason:

> Sender address rejected: Domain not found (in reply to RCPT TO command)

It seems that roundcube add a localhost to the from header.

I can see from=<myusername@localhost.MYREALDOMAIN.org>

Any idea on how to solve it?

How to remove that localhost?

postconf -n

[root@netstar roundcubemail]# postconf -n
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
always_bcc = MYUSERNAME@MYREALDOMAIN.org
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
debug_peer_level = 2
home_mailbox = Maildir/
html_directory = no
inet_interfaces = $myhostname, localhost
inet_protocols = all
mail_owner = postfix
mailbox_size_limit = 1024000000
mailbox_transport = lmtp:unix:/var/spool/postfix/private/dovecot-lmtp
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
message_size_limit = 102400000
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
mydomain = MYREALDOMAIN.org
myhostname = mail.MYREALDOMAIN.org
mynetworks = 192.168.0.0/24, 127.0.0.0/8
myorigin = $myhostname
newaliases_path = /usr/bin/newaliases.postfix
queue_directory = /var/spool/postfix
readme_directory = /usr/share/doc/postfix-2.6.6/README_FILES
recipient_bcc_maps = hash:/etc/postfix/bcc_maps
relay_domains =
sample_directory = /usr/share/doc/postfix-2.6.6/samples
sender_bcc_maps = hash:/etc/postfix/bcc_maps
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtpd_delay_reject = yes
smtpd_helo_required = no
smtpd_helo_restrictions = permit_mynetworks,    permit_sasl_authenticated,    permit
smtpd_recipient_restrictions = permit_mynetworks,   permit_sasl_authenticated,   reject_unauth_destination,   check_sender_access hash:/etc/postfix/sender_access,   reject_rbl_client zen.spamhaus.org,   permit
smtpd_sasl_auth_enable = yes
smtpd_sasl_path = private/auth
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_sender_restrictions = permit_mynetworks,    permit_sasl_authenticated,    reject_non_fqdn_sender,    reject_unknown_sender_domain,    reject_unauth_destination,    permit
smtpd_tls_auth_only = yes
smtpd_tls_cert_file = /etc/pki/tls/certs/mail.MYREALDOMAIN.org.cert
smtpd_tls_key_file = /etc/pki/tls/private/mail.MYREALDOMAIN.org.key
smtpd_tls_loglevel = 1
smtpd_tls_security_level = may
smtpd_tls_session_cache_database = btree:/var/spool/postfix/smtpd_tls_cache
smtpd_tls_session_cache_timeout = 3600s
tls_random_source = dev:/dev/urandom
unknown_local_recipient_reject_code = 550