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SQL Server Agent

SQL Server Agent is a Windows service. This service executes what is referred to as jobs and alerts.
SQL Server Agent stores the information it needs to schedule and execute its jobs and alerts in the msdb system database.
The SQL Server Agent service is disabled on instances of SQL Server Express and SQL Server Express with Advanced Services.
Account name: NT Service\SQLSERVERAGENT
Executable: SQLAGENT.EXE
Startup dates (and times) of the SQL Server Agent Service are recorded in the msdb.dbo.syssessions table.

See also

SQL Server services
The registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\instance name\SQLServerAgent

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