I have a Windows Server 2008 R2 server running Exchange Server 2010 with multiple accepted domains.
The main domain (mescorp.com.au) on which the server is built can send and receive emails from external and internal
The other accepted domain (thevixengroup.com.au) which is totally different can send and receive internally but can only send externally.
mail.thevixengroup.com.au is pointing to the same IP as mail.mescorp.com.au
Email address policy's have been configured for both domains and both have been applied. mescorp.com.au is priority 1 and thevixengroup.com.au is priority 2
Why would mescorp.com.au work and thevixengroup.com.au not work?