For some reason, the default number of ERRORLOG files maintained by SQL Server defaults to six. This has always seemed like a poor choice to me, as it makes it impossible to investigate events that may have occurred many months ago. Fortunately, this is a simple Registry setting, and we can use the undocumented xp_instance_regwrite system stored procedure to set it to the value we want.
------------------------------------------------------------------------------- -- Set the number of ERRORLOG files to the maximum value of 99 instead of the -- default of 6. This is especially useful if you also set up a Job to cycle -- the ERRORLOG files every week or so, to keep them small enough to load -- comfortably. ------------------------------------------------------------------------------- EXEC xp_instance_regwrite N'HKEY_LOCAL_MACHINE', N'Software\Microsoft\MSSQLServer\MSSQLServer', N'NumErrorLogs', REG_DWORD, 99 GO
See this SQLAdmin post at xp_instance_regwrite syntax for details on how to use that procedure.
