Configuring Exchange Server 2007 to send/receive external email

As we know, a server installed as the mailbox role cannot be ran as a edge server. So we need some other 3-part components to bear these tasks. But what i want to say is, if you are running everying thing(domain controller,dns server,exchange server) on a single server,there is really simple ways doing this.

1. Receiving external emails:

Creat MX record in your dns control panel, and then run the script:"Set-ReceiveConnector -Identity "Default <ServerName>" -PermissionGroups "AnonymousUsers"" in the exchange shell.

2.Sending external emails:

Set a smtp connector in the exchange control panel and creat the policy(to send all the out-going mail or depends on domain).

Go test your mailbox now.