SQLMai and SQLAgentMail
If were managing a single server or two, alerts and notifications may not be a big deal to us (though Id still be debating that alerts and notifications are invaluable here, too). But if were managing multiple boxes, were very reliant on automatically generated messages from the servers to let us know whats going on (or at least, if we do, our job again becomes easier).
Heres where SQLMail and SQLAgentMail come in.
Its SQLAgentMail that sends out alerts and notification via e-mail. However, if there is a need to run SQLMail as well (this can be very handy if we want to process queries by e-mail or send an e-mail in a batch job or stored procedure), then its usually best to use the same user account for both MSSQLServer (which uses SQLMail) and SQLServerAgent (SQLAgentMail). This means only one mailbox has to be created on the mail server and only one profile has to be set up on the SQL Server itself. By the way, this is the recommended practice by Microsoft, according to Books Online.