Creating a new send connector in Exchange 2010

Use the EMC to create a Send connector

You need to be assigned permissions before you can perform this procedure. To see what permissions you need, see the "Send connectors" entry in the Transport Permissions topic.

1. Open the Exchange Management Console. Perform one of the following:
   • On a computer that has the Edge Transport server role installed, select Edge Transport, and then in the work pane, click the Send Connectors tab.
   • To create a Send connector on a Hub Transport server role, in the console tree, expand Organization Configuration, select Hub Transport, and then in the work pane, click the Send Connectors tab.
2. In the action pane, click New Send Connector. The New SMTP Send Connector wizard starts.
3. On the Introduction page, follow these steps:
   1. In the Name field, type a meaningful name for this connector (example:  ETRN Outbound Connector). Specify a name for the Send connector that helps you distinguish this Send connector from other Send connectors in your configuration.
   2. In the Select the intended use for this connector field, select the usage type for the connector. The usage type determines the default permission sets assigned on the connector and grants those permissions to trusted security principals.
      Select Custom: Select this option to create a customized connector to connect with systems that aren't servers running Exchange 2010.
      Click Next.
4. Address space:, specify an address space to which the Send connector sends mail. If routing all email through ETRN, enter *
5. Smarthost Address:  Use host <domain-com>-smtp.etrn.com – Replace domain-com with your entire domain name, substituting '-' for '.'

Read the entire Microsoft KB article here.