The SQL Server Agent XPs Disabled alert indicates that the Agent XPs configuration option is disabled in SQL Server 2005 or later versions. The alert may also signal that procedures are dropped in SQL Server 2000 for the SQL Server instance. Note that SQL Diagnostic Manager does not collect SQL Agent job details.
Agent XPs are disabled when SQL Server Agent is stopped. You can re-enable Agent XPs through the Server Configuration view and allow viewing of agent job histories even when the agent is not running.