How to Turn On and Start Lion Mail Service with Server Admin
When you throw the e-mail On switch in the Server app in Lion Server, it both enables mail service and turns it on. With Server Admin, you have to enable the service and then start it running.
You can tell whether Mail is turned on and running in Server Admin by going to the left column and clicking the triangle to the left of your server to expand the list of services. If Mail isn’t included in the list, it isn’t enabled. If Mail appears but the circle is empty, Mail is enabled but isn’t started.
To enable mail service with Server Admin, do the following:
Select your server in the column on the left.
Click the Settings icon in the toolbar; then click the Settings tab.
Select the Mail check box and click Save.
If you ever decide to stop using Mail Server, it’s a good idea to go back here and disable it. This is the only way to do so in Lion Server.
To start the Mail service:
Click the triangle to the left of your server to expand the list of services and then click Mail.
Click the Start Mail button in the lower left of the screen.
Of course, there’s much more you can do with Server Admin to configure mail service, but at this point, it’s easier to do the rest of your configuration with Configuration Assistant.