While starting SMTP could not initialize its security.
To resolve this issue execute the following steps:
This step-by-step article describes how to set Simple Mail Transfer Protocol (SMTP) virtual server security options. You can select the security levels for the SMTP virtual server and use the security options to obtain the level of protection that you require. The settings that you configure on the security tabs apply to all domains on the virtual server.
http://support.microsoft.com/default.aspx?scid=kb;EN-US;324285