To use the email server, you need to change the host to the public DNS name you plan on assigning to the FME Server. For example, if you are using an AMI the host name could be ec2xxxx.amazon.com but the public DNS name may be demo.safe.com. You want to set the Email host name to the second one in this case.
To change the name, open this file:
<FME Server Install DIR>\Utilities\smtprelay\james\apps\james\SAR-INF\config.xml
Find the following tags:
<postmaster>Postmaster@localhost</postmaster>
<servername>localhost</servername>
Update to the public DNS:
<postmaster>Postmaster@alertdemo.safe.com</postmaster>
<servername>alertdemo.safe.com</servername>
Restart the FME Server SMTP Relay service.
If you wish to make the email server accessible to the Internet the following ports must be open: