Because loads of questions pop up without any good information given to solve the problem, i decided to do it "before" you ask for it. Works faster, and better. information. 25/tcp open smtp Postfix smtpd 110/tcp open pop3 Qualcomm Qpopper MX mail dns highrc.net email ip 62.251.8.45 local ip 10.0.0.152 (forwared by router, port 25, 110) Postfix version 2.0.19-20040312 the postconf -n is as the following. alias_maps = hash:/etc/aliases best_mx_transport = local canonical_maps = hash:/etc/postfix/canonical_new command_directory = /usr/sbin config_directory = /etc/postfix daemon_directory = /usr/lib/postfix debug_peer_level = 2 defer_transports = disable_dns_lookups = no mailbox_size_limit = 0 mailq_path = /usr/bin/mailq manpage_directory = /usr/share/man masquerade_classes = envelope_sender, header_sender, header_recipient masquerade_exceptions = root message_size_limit = 10240000 mydestination = $myhostname, localhost.$mydomain, $mydomain mydomain = highrc.net myhostname = www.highrc.net myorigin = $mydomain newaliases_path = /usr/bin/newaliases readme_directory = /usr/share/doc/packages/postfix/README_FILES relay_domains = $mydestination sample_directory = /usr/share/doc/packages/postfix/samples sendmail_path = /usr/sbin/sendmail setgid_group = maildrop smtp_sasl_auth_enable = no smtp_use_tls = no smtpd_helo_required = yes smtpd_sasl_auth_enable = no smtpd_use_tls = no strict_rfc821_envelopes = no unknown_local_recipient_reject_code = 450 virtual_alias_maps = hash:/etc/postfix/virtual What im trying to do it set up a mail server, wich half succeeded. The mail server is running and the MX domain is pointed to my server. Ive successfully created user accounts, these can log in with pop/smtp and retrieve mail. (But also i got a webmail variant "Gossamer mail" running. wich logs into the pop box/smtp from local) The smtp recieves mail, from outsite. so its only the "sending" part from the client thats trying to send mail. Ive tried it myself from local (10.0.0.151) and i had no problems on the email accounts i tried sending mail with. So i think this is a problem with the internet/local routing. First i had 2 error messages, i got it reduced to 1. This was the error. Protocol: SMTP, Reactie van server: '554 <endymion2k4@gmail.com>: Recipient address rejected: Relay access denied', Poort: 25 I noticed on my local network the dns "highrc.net" wasnt bounded to my ip so i changed that. Now i got this error. Protocol: SMTP, Reactie van server: '554 <endymion2k4@gmail.com>: Relay access denied', Poort: 25 I tried changing the relay things in postfix but it didnt work. i always got that error. Thanks in advance Servers are linux, Workstations are windows.