220 Warning: no name found in DNS for your host address During the initial greeting in a telnet session to your Mail Server the following message is seen after the initial greeting: 220-domain.com MailSite ESMTP Receiver Version 5.3.4.1 Ready -->220 Warning: no name found in DNS for your host address<--
To resolve this issue you need to ensure that you enter a fully qualifying host name within your network settings:

1. Get the properties for My Computer, next click the tab; Network Identification.
2. Click the properties button
3. Under Computer name specify the HOST / Computer (example; mail)
4. Next click the More button
5. Where it says, "Primary DNS suffix of this computer; enter your primary domain name.
6. Click OK and OK again

Note: A Server reboot is usually required when making such changes