E-mail issues

I know this has been beat to death but I am unable to find a definitive answer to this.

Asterisk v

I was looking around trying to figure out why no e-mails are going out for updates, voicemail and so on. So I am looking around in webmin and I look at my Postfix mailserver tab to find a bunch of mail waiting to go out but with an error of timed out.

This I presume is due to the fact that the e-mails are coming from a domain that is not a real domain and a user of the same? [email protected]

So I attempted to setup the outgoing server as my cPanel e-mail username in an attempt to use it as a proxy of sorts, still no luck.

Anyone shed some light on this for me? I am still a bit of a linux and freepbx noob.

Many thanks.