[cobalt-users] DNS and Mail - User unknown

["Jeffrey M. Nunes" <jmn@xxxxxxxxxx>]

I am having a problem with MAIL and DNS's. 

I have several domains on a cobalt RaQ550. 

I am not using the internal DNS I have an external DNS setup.

I have 1 domain on the cobalt that has an external mail server (Exchange).

I have the MX records on the external DNS set to us the Exchange Server.

Everyone from the outside world can send e-mails to that domain fine, but when a domain from the cobalt sends an e-mail. A bounce back happens. The bounce back says 

The user is unknown.

I think the senders e-mail is not leaving the Cobalt. How can I fix this.

Any help or suggestions would be great.

Thanks all

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