Just added an additional domain to our network. I have a few users that need to accept emails from several different domains. If I send them an email from an internal email address it works just fine. They receive it in their inbox. If i send them from an external account IE Gmail. It doesn't make it to their inbox. I do believe the emails are arriving at our location. We are utilizing a barracuda spam firewall that receives the mail and then forwards to our exchange server. The barracuda says that it has delivered the message. Is there somewhere within exchange where I need to authorize them to receive emails from outside accounts?