554 5.1.2 Recipient address rejected: User unknown
I have looked around the forums but haven't found the answer to my problem, but apologies if this duplicates an error.
I am trying to configure SMG to relay messages from a particular set of IP address' to both local and non-local domains. The local domains work fine, but sending to non-local (*@ gmail.com for example) does not work. I get 554 5.1.2 Recipient address rejected: User unknown.
The local domains are configured under Protocol>Domains, but I do not know how to allow SMTP email to non-local domains. Using the built in tools I am able to do an MX lookup for gmail.com, but beyond this I'm stumped.
Can anyone suggest what I might be doing wrong please?