SQL Server Log Files

SQL Server Log Files: SQL Server has two log files, which provide useful troubleshooting information. They are usually located in the …\Microsoft SQL Server\Log directory (or MSSQL\Log).  This directory is usually located under the same root directory where the databases are installed.

• ErrorLog: The main log file contains all connection messages and error reporting since SQL Server was started.  Depending on the setup, the output SQL Trace flags may be reported here (i.e. if DBCC 3605 is enabled).  Old log files are sequentially assigned an integer extension.

• SQLAgent.Out: The other log contains messages and error reporting for the MSSQL SQLAgent service.  Among other things, the SQLAgent is responsible for running backups and other jobs.  It should be checked if there are problems with any scheduled task.

For more information, please see your SQL Server Books Online.