In addition to starting SQLMail automatically when SQL Server starts, SQLMail can be started and stopped manually from the query interface. Only the SA can start and stop SQLMail.
If you do not start the Windows NT Mail client before starting SQLMail, you will not be able to view the Inbox/Sentmail during that SQLMail session. The Windows NT Mail client cannot be started after SQLMail starts.
xp_startmail ['user'] [, 'password']
where
If no user or password are provided, SQL Server uses the username and password specified in the Mail Login dialog box. If user and password are provided, SQL Server attempts to log on to Windows NT Mail (or other MAPI provider) by using that username and password. If user and password are provided but are incorrect, an error message is returned.
xp_stopmail
For more information about the Mail client interface, see your documentation for Microsoft Windows NT, or see the Microsoft Windows NT Resource Kit.