From what I understood from my searches, to avoid the "Access denied - Invalid HELO name (See RFC2821 220.127.116.11)" when sending emails using the SMTP on a 2008 R2 server, its FQDN must be set and to enter it I do the following:
- Open IIS 6.0 Manager
- Click on the server name then right click on SMTP virtual server and select properties
- Click on Delivery tab then Advanced
At this point there is a text box that says "Fully qualified domain name". The server name is SERVER2 and the fixed i.p. is 206.xxx.xxx.5 What should I enter there ? I don't have a DNS to point to. I tried SERVER2.206.xxx.xxx.5 but when I clicked the "Check DNS" button it says it is invalid.