One need to perform below mentioned steps whenever wants to activate SMTP service from windows 2003 server:
1) Open control panel of Windows 2003 server.
2) Click on Add/Remove programs.
3) Click on Add/Remove Windows Components.
4) Click on Internet Information System [IIS] and click on details button.
5) Select the check box against SMTP service.
6) Click on OK and complete the procedure.
After the installation of the SMTP service on Windows Server 2003, the SMTP tree may not appear in the IIS Manager console. To resolve this issue there are two alternative procedures:
Click the "Start" button, then Run and type:
Alternatively, %systemroot% can be replaced with the drive name on which Windows Server 2003 is installed.
Uninstalling and re-installing IIS including the SMTP service which may resolve the issue.