2. Browse to the Delivery tab, and click the Advanced button:
3.In the Smart Host field, enter the FQDN on your SonicWALL Email Security appliance (such as, esa.example.com). Note: The Exchange Server must be able to resolve this host name.
4. Click OK
On your SonicWALL Email Security appliance, in the Server Configuration > Network Architecture page, configure a separate, outbound path to handle the outbound email flow at the appliance.
Configure the path to use the MTA (MX routing or SmartHost) under Destination of Path.
You need to configure something unique between the Inbound and outbound path to distinguish Inbound from outbound mail flow. A very simple way to do this is to have them listen on different ports or enter the IP address of the Exchange Server as the Source IP Contacting Path on the outbound path.
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