Question : Host unknown (Name server: mail.domain.com: host not found)

550 ... Host unknown (Name server: mail.domain.com: host not found)

OS is Solaris 8 , sendmail 8.9

When reply back yo [email protected] ,it bounces back with this error.

Answer : Host unknown (Name server: mail.domain.com: host not found)

If your Domain properly registered in DNS? Does DNS have an MX record pointing to the correct mailserver for your Domain? Is that mailserver properly registered (the name to which the MX record points should be an A record, *not* a CNAME record)?

Also, please be clearer on your situation. Is this when an external client sends an E-Mail to your Domain? Or when you, sitting in front of a terminal session onthe Solaris 8 server, try to send an E-Mail to your Domain, or what? Help us help you by taking some time to *fully* describe your situation.