When any critical error / warning is reported by SQL Server Agent, it is written to a log file MSSQL\Log\SQLAgent.out.  By default only critical errors and warnings are reported to this log file. If you would like to see additional information messages, here are the steps you could follow to enable verbose tracing

1) Launch Agent Properties dialog

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2) Turn on “Include execution trace messages”; Click Ok

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3) Restart  SQL Agent and View Current Agent Error Log

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If you no longer need verbose turning you can turn off this option. When you see any errors in SQL Agent that is harder to trouble shoot, please turn on this option and report this log file to http://connect.microsoft.com . Detailed verbose logs would be useful for our development team during bug investigation process.

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