We have an application server that hosts a CRM application. It is using SMTP on it's own server to send emails. If I send an email using the application to me@MyPersonalDomain.com, it shows up in my inbox. If I send an email to AnyAddress@MyCompanyDomain.com, it never shows up. It doesn't matter what address I put in for @MyCompanyDomain.com, they never get through. Any email addresses outside our domain/firewall get through.
We're using Exchange 2007 and when I look at the message tracking logs, the missing messages don't show up there, either.
Is there something I need to configure in Exchange or the SMTP server on the application server? I can't figure out why emails get outside the firewall but internal emails never show up.