SQL Mail is removed from SQL Server 2012 as Microsoft promised in SQL 2008’s BOL. Configuration “SQL Mail XPs” is removed from SQL 2012, check sp_configure in SQL Server 2012. Supporting procedures are removed as well. Those procedures are removed from master database xp_startmail, xp_stopmail, xp_findnextmsg, xp_readmail, xp_deletemail, xp_sendmail, and sp_processmail. Ensure your SQL Server applications do not use them anymore. If do, have those contract procedures handy before upgrading SQL Servers to 2012.
SQL Mail Removed in SQL Server 2012