I'm having trouble sending mail to certain e-mail addresses, including anyone who is a Time Warner RR customer or employee. I've narrowed the problem down to the fact that the messages are being sent from firstname.lastname@example.org instead of the contact e-mail specified in phpBB. This is what I'm seeing in my logs: Jul 30 00:57:46 localhost postfix/smtp: 6EB2C690042: host clmboh-02.mgw.rr.com[18.104.22.168] said: 451 #4.1.3 Domain of sender address <email@example.com> does not resolve (in reply to MAIL FROM command) I had the same exact site running on a Site5 server before I moved it a few days ago just fine, and it would send e-mail to those same folks. It's the first site I've moved to this dedi that's running ISPConfig, and I thought I was ready to go. Please help!