I have ISPConfig 3 set up with several domain names. I am on a dynamic IP which is blacklisted by SpamHaus so I followed another HowTo here to relay thru an email server account I have elsewhere. Now I can send emails from my local accounts without getting rejected. But I can not receive emails. If sent to a yahoo account, yahoo receives ok. Trying to reply gives... Code: Hi. This is the qmail-send program at yahoo.com. I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out. <[email protected][email protected][email protected][email protected][email protected][email protected][email protected] If I send a message to an email address on the server I'm relaying thru 2 copies arrive. When I reply I get a copy of the response and 2 copies of the following failure message... Code: This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: admin@nonexistent_example.com (ultimately generated from [email protected][email protected][email protected][email protected][email protected][email protected][email protected] That I'm getting 2 copies and an email address in the message that shouldn't exist (admin@nonexistent_example.com) makes me thing there is a forwarder set up at my offsite ISP. I do not have one set up and they haven't responded. I seem to have my local DNS and MX records set up. I changed /etc/postfix/main.cf line MYDESTINATIONS to point to a file called local-host-names, then added all my domains to that file (including mail.domain.com). So does this appear to be a local problem or a problem at my relay ISP? Does the relaying only affect sending mail (which seems to work ok) or can it mess with my receiving mail as well? ... I changed the email addresses and domains in the examples to avoid spam bots, the actual local mailserver domain is host.servidora.net, and a domain I'm trying to receive at is sys666.net. Thanks for any pointers, you guys are great.