The most common error that we see in setting up email alerts is this one:
SQL Server blocked access to procedure'sys.xp_sendmail' ol component 'SQL MailXP's because this component is turned off as part of the security configuration for this server.
Get on the SQL server as 'sa' and run this script:
sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'SQL Mail XPs', 1;
GO
RECONFIGURE;
GO