Nlog IsError false and isInfo

I have NLog.config looks like

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://ift.tt/1jYW9iS;
      xmlns:xsi="http://ift.tt/Atvu06;       >

  <variable name="logDirectory" value="${specialfolder:folder=ApplicationData}/ErrorLog"/>
  <variable name="archiveDirectory" value="${specialfolder:folder=ApplicationData}/ErrorLog/archives/${shortdate}"/>
  <variable name="defaultFileName" value ="normal_log_"/>
  <variable name="defaultErrorFileName" value ="errors-log_"/>

  <targets async="true">
    <target name="console" xsi:type="Console" layout="${longdate} | ${level} | ${callsite} | ${message}" />
    <target name="default" xsi:type="File" layout="${longdate} | ${level} | ${callsite} | ${message}" fileName="${logDirectory}/${defaultFileName}{#}.txt" archiveFileName="${archiveDirectory}/${defaultFileName}{#}.txt" archiveEvery="Day" archiveNumbering="Rolling" maxArchiveFiles="7" />
    <target name="errors" xsi:type="File" layout="${longdate} | ${level} | ${callsite} | ${message}" fileName="${logDirectory}/${defaultErrorFileName}{#}.txt" archiveFileName="${archiveDirectory}/${defaultErrorFileName}{#}.txt" archiveEvery="Day" archiveNumbering="Rolling" maxArchiveFiles="7" />
  </targets>

  <rules>
    <logger name="*" writeTo="default" />
    <logger name="*" writeTo="console" minlevel="Info" />
    <logger name="*" writeTo="errors" minlevel="Error" />
  </rules>



</nlog>

and I use it like

public static class Log
{
    private static Logger logger;

    static Log()
    {
         logger = LogManager.GetCurrentClassLogger();              
    }

    public static void LogError(Exception ex)
    {
        logger.Error<Exception>(ex);
    }

but nothing is written to App_Data\errorlog . after debugging I noticed that all of its properties is false

any idea how to fix that