Mail Host Database
The msdb database is the Database Mail host database. This database contains the stored procedures and messaging objects for Database Mail. Microsoft SQL Server Management Studio includes the Database Mail Configuration Wizard for enabling Database Mail, creating and managing profiles and accounts, and configuring Database Mail options.
By default, Database Mail is not active. To use Database Mail, you must explicitly enable Database Mail by using either the SQL Server Surface Area Configuration tool or the Database Mail Configuration Wizard.
For a list of the views and stored procedures that are associated with Database Mail, see Database Mail Messaging Objects.
Service Broker must be enabled in the msdb database. However, Database Mail does not use Service Broker networking. Therefore, users do not have to create a Service Broker endpoint to use Database Mail. The external Database Mail process uses a standard ADO.NET connection to communicate with SQL Server. For information about how to enable Service Broker in a database, see How to: Activate Service Broker Message Delivery in Databases (Transact-SQL).
Other ResourcesHow to: Activate Service Broker Message Delivery in Databases (Transact-SQL)
Introducing Service Broker