I have a Windows 2003 server using IIS and SMTP to send emails to the Internet. This server (we'll call it REJECTEDSERVER) is used to as an SMTP server for 3 other servers in the same location. The REJECTEDSERVER however is not on our domain nor will it ever be but we can access it across our WAN.
Recipients are not receiving their emails so we're getting undeliverables:
Your message did not reach some or all of the intended recipients.
Sent: 4/8/2010 2:58 PM
The following recipient(s) could not be reached:
firstname.lastname@example.org on 4/8/2010 2:58 PM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<REJECTEDSERVER #5.5.0 smtp;504 <REJECTEDSERVER>: Helo command rejected: need fully-qualified hostname>
How can I allow REJECTEDSERVER to successfully send mail without being on our domain?