Click the Program link near the left hand side of the page.
Click the Programs link near the top of the page.
Click the Expert Rules link near the top of the page.
We will list a series of lines here that will show you exactly how to setup Zone Alarm's firewall for 1st SMTP Server. Go ahead and enter the settings shown below into the Add Rule menu.
When you are finished, click the Ok button at the bottom of your screen. And that is it! You are done!