Environment: ubuntu 8.04.1/Postfix Problem: Can send if on-box can receive off-box w/WinXP-Thunderbird can send if off-box sending to default domain for box. can NOT send from off-box to any other domain Other info: /var/log/mail.log says QUEUE: reject:....... Relay access denied; from=<<user>@<defaultdomain.tld>> to=<<anyuser>@gmail.com> proto=ESMTP helo=<[192.168.1.106}> I'm sure that I'm missing something obvious, but . . . HELP?