Open Relay Spam Issue

[joefromjersey300]

I am running Imail Version 7.13

We have gotten blacklisted as a spammer. I didn't set up this server and I am more familiar with Exchange than Imail.
I need to close my open relay. I know what a relay is and how to close them in Exchange but not in Imail.
I have researched this here and I am supposed to either do: relay for IP addresses or no mail relay.
1. I don’t know which to do?
2. I don’t know how to do either b/c I don’t see this in the controls to do either?

http://support.ipswitch.com/kb/IM-19980116-JB02.htm

My clients connect via web based clients (internal and external) and outlook and outlook express clients (internal and external)
How do I fix this and get off the Blacklists? For various organizational reasons we can’t upgrade to the latest version of Imail.

 

[NCBrit]

The most secure way is to set your mail relay options under the smtp security tab to relay for local users only. This will make it so that all of your outlook/outlook express clients have to authenticate to send mail.

To find this tab, open the imail administrator, expand the services folder, click on smtp, then you will see there is an smtp security tab available.