Hi, Getting this when sending to one domain on a server. SMTP error from remote mailer after RCPT TO:<firstname.lastname@example.org>: host address.net [ip.ip.ip.ip]: 550-"The recipient cannot be verified. Please check all recipients of this 550 message to verify they are valid." /etc/localdomains is fine I've run all the ususal scripts - no joy. I've reinstalled exim - no joy. The exim log says simply rejected RCPT <email@example.com>: Any ideas ?