EPiServerLog.config

<?xml version="1.0" encoding="utf-8"?>

<log4net>

  <appender name="errorFileLogAppender" type="log4net.Appender.RollingFileAppender">
    <file value="C:\EPiServer\Logs\Screentek.EPi.Imageshop\EPiServerErrors.log" />
    <encoding value="utf-8" />
    <staticLogFileName value="true" />
    <datePattern value=".yyyyMMdd.'log'" />
    <rollingStyle value="Date" />
    <threshold value="Error" />
    <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    <appendToFile value="true" />
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %level %logger: %message%n" />
    </layout>
  </appender>

  <appender name="outputDebugStringAppender" type="log4net.Appender.OutputDebugStringAppender">
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="[%thread] %level %logger: %message%n" />
    </layout>
  </appender>

  <!-- Reduce amount of debug logging -->
  <logger name="EPiServer.Core.OptimisticCache" additivity="false">
    <level value="Error" />
    <appender-ref ref="errorFileLogAppender" />
  </logger>
  <logger name="EPiServer.Core.ContentProvider" additivity="false">
    <level value="Error" />
    <appender-ref ref="errorFileLogAppender" />
  </logger>
  <logger name="EPiServer.Data.Dynamic.Providers.DbDataStoreProvider" additivity="false">
    <level value="Error" />
    <appender-ref ref="errorFileLogAppender" />
  </logger>
  <logger name="EPiServer.Data.Providers.SqlDatabaseHandler" additivity="false">
    <level value="Error" />
    <appender-ref ref="errorFileLogAppender" />
  </logger>
  <logger name="EPiServer.Data.Providers.ConnectionContext" additivity="false">
    <level value="Error" />
    <appender-ref ref="errorFileLogAppender" />
  </logger>

  <root>
    <!--Be careful, setting this value to All, Debug or Info will affect performance.-->
    <level value="Error" />
    <!--Enabled file logging-->
    <appender-ref ref="errorFileLogAppender" />
    <!-- Use DebugView (Microsoft/SysInternals) and enable Capture Win32 + Capture Global Win32 (http://technet.microsoft.com/en-us/sysinternals/bb896647). -->
    <!--appender-ref ref="outputDebugStringAppender" /-->
  </root>

</log4net>