AdjustFileBeforeAppend() NullReferenceException

Application: Synovia.Service.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.NullReferenceException
   at log4net.Appender.RollingFileAppender.AdjustFileBeforeAppend()
   at log4net.Appender.RollingFileAppender.Append(log4net.Core.LoggingEvent)
   at Synovia.Service.Common.Common.Logging.AsyncFileAppender.LogMessages()
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Threading.ThreadHelper.ThreadStart()

<log4net>
    <root>
      <level value="ALL" />
      <appender-ref ref="asyncForwarder" />
    </root>


	<appender name="asyncForwarder" type="Log4Net.Async.ParallelForwardingAppender,Log4Net.Async">
      <appender-ref ref="LossyAppender" />
      <appender-ref ref="LogFileAppender" />
	  <bufferSize value="2147483644" />
    </appender>
	
    <appender name="LossyAppender" type="log4net.Appender.BufferingForwardingAppender">
      <bufferSize value="200" />
      <lossy value="true"/>
      <evaluator type="log4net.Core.LevelEvaluator">
        <threshold value="WARN"/>
      </evaluator>
      <appender-ref ref="LogglyAppender" />
	</appender>
	 <appender name="LogglyAppender" type="log4net.loggly.LogglyAppender, log4net-loggly">
      <rootUrl value="https://logs-01.loggly.com/" />
      <inputKey value="?????" />
      <tag value="GOLD_M1_S1" />
	  <filter type="log4net.Filter.LevelRangeFilter">
        <levelMin value="WARN" />
        <levelMax value="FATAL" />
      </filter>
    </appender>
	
    <appender name="LogFileAppender" type="Synovia.Service.Common.Common.Logging.AsyncFileAppender">
      <lockingModel type="log4net.Appender.FileAppender+ExclusiveLock" />
      <file value="logs\" />
      <datePattern value="dd.MM.yyyy'.log'" />
      <appendToFile value="true" />
      <rollingStyle value="Composite" />
      <maxSizeRollBackups value="20" />
      <maximumFileSize value="200MB" />
      <staticLogFileName value="false" />
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date{MM/dd/yyyy HH:mm:ss.fffffff}|%logger|%thread|%-5level|%message|%newline" />
      </layout>
    </appender>

  </log4net>