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Log4net doesn't show exact error message

I'm using log4net as a global exception handler in my .NET Core 2.0 app.
I need to show exact error message and stacktrace. But at the moment it just say "An unhandled exception has occurred while executing the request"
This is my log4net configuration:
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
<appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
<file value="logger.log" />
<appendToFile value="true" />
<maximumFileSize value="100KB" />
<maxSizeRollBackups value="2" />
<layout type="log4net.Layout.PatternLayout">
<IgnoresException value="False" />
<conversionPattern value="%date %logger [%thread] [%ndc] (%file:%line) %level- %message%newline"/>
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="RollingFile" />
</root>
</log4net>
</configuration>
How I can show exact error message and stacktrace?

How to configure log4net to log into multiple files

I have a windows service application which is basically a solution created with VS2015 and contains 2 projects.
The first project is dealing with the service itself (start, stop, etc) while the second one is maintaining the process that will be executed due to launch of the service.
I am using the log4net to log messages into a file.
I wanted to created 2 separate log files for each project.
This has been configured into the service project and is up and running.
while it is not working for the second project.
So mainly my question is how to configure log4net to log into different files within one solution?

Configure log4net within the executing project only. If you want log messages from an specific assembly logged to a separate file make sure the root namespace for that assembly is unique and define two log4net appenders, each logging to a separate file and use logging filters to filter by namespace.
<!-- Will log only from the My.Process namespace -->
<appender name="ProcessLog" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LoggerMatchFilter">
<loggerToMatch value="My.Process" />
<acceptOnMatch value="true" />
</filter>
<filter type="log4net.Filter.DenyAllFilter" />
<file value="process.log" />
<!-- layout, etc -->
</appender>
<!-- will log everything except from the My.Process namespace -->
<appender name="ServiceLog" type="log4net.Appender.RollingFileAppender">
<filter type="log4net.Filter.LoggerMatchFilter">
<loggerToMatch value="My.Process" />
<acceptOnMatch value="false" />
</filter>
<file value="service.log" />
<!-- layout, etc -->
</appender>
And don't forget to add a reference to both appenders in the root element.

Assuming your first and second project have different root namespaces (e.g. Project1.Service and Project2.MaintainProcess), you can use 2 appenders and the logger hierarchy to split the log files by project:
<log4net>
<appender name="Project1Logger" type="log4net.Appender.RollingFileAppender">
<file value="Project1Logger.log" />
</appender>
<appender name="Project2Logger" type="log4net.Appender.RollingFileAppender">
<file value="Project2Logger.log" />
</appender>
<root>
<level value="ALL" />
</root>
<logger name="{Project1RootNamespaceHere}">
<appender-ref ref="Project1Logger" />
</logger>
<logger name="{Project2RootNamespaceHere}">
<appender-ref ref="Project2Logger" />
</logger>
</log4net>
If you don't want to use separate appenders and logger hierarchy then see this answer for an alternative method using a custom pattern substitution to use a single appender. I'm not sure of the performance implications of that approach though.

Complete configuration (with a MinimalLock file appender):
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.2" />
</startup>
<log4net>
<!-- ALL, DEBUG, INFO, WARN, ERROR, FATAL, OFF -->
<appender name="RollingFileAppender_Info" type="log4net.Appender.RollingFileAppender">
<file value="Info.log" />
<encoding value="utf-8" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="100MB" />
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message %exception%newline" />
</layout>
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="DEBUG" />
<levelMax value="WARN" />
</filter>
</appender>
<appender name="RollingFileAppender_Error" type="log4net.Appender.RollingFileAppender">
<file value="Error.log" />
<encoding value="utf-8" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="100MB" />
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message %exception%newline" />
</layout>
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="ERROR" />
<levelMax value="FATAL" />
</filter>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="RollingFileAppender_Info" />
<appender-ref ref="RollingFileAppender_Error" />
</root>
</log4net>
</configuration>

log4net not logging errors and fatal in separate file

I tried to separate the errors and fatal into separate log file not i dont see it logging in separate file. here is my config file. can you point what mistake i made?
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file type="log4net.Util.PatternString" value="C:\NinjaTraderLogs\NinjaLogs.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="5" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level (%property{method}) (%property{state}) (%property{instrument}) - %message%newline" />
</layout>
<level value="All" />
</appender>
<appender name="FatalError" type="log4net.Appender.RollingFileAppender">
<file type="log4net.Util.PatternString" value="C:\NinjaTraderLogs\NinjaLogs_Fatal.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="5" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level (%property{method}) (%property{state}) (%property{instrument}) - %message%newline" />
</layout>
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="ERROR" />
<levelMax value="FATAL" />
</filter>
</appender>
<root>
<appender-ref ref="RollingFileAppender" />
</root>
</log4net>
</configuration>

Create one more appender ref as below under <root>
<root>
<appender-ref ref="RollingFileAppender" />
<appender-ref ref="FatalError" />
</root>
Before you call your logging in code make sure to call the XmlConfigurator function Configure (call it globally) like
log4net.Config.XmlConfigurator.Configure();
Last but not least, make sure you have write permission to the directory you are trying to create log file. I would suggest you to check windows event log once Application log to see if any error has happened.

log4net is not creating log file to log

log4net is not creating any text file to log. I tried like this
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>
<log4net>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file type="log4net.Util.PatternString" value="EpinovaADSyncJob.log" />
<appendToFile value="false" />
<rollingStyle value="Composite" />
<staticLogFileName value="false" />
<datePattern value="yyyy-MM-dd" />
<preserveLogFileNameExtension value="true"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %level %logger - %message%newline%exception" />
</layout>
</appender>
<root>
<level value="INFO"/>
<appender-ref ref="RollingFileAppender"/>
<appender-ref ref="ConsoleAppender" />
</root>
</log4net>
</configuration>
In assembly file:
[assembly: log4net.Config.XmlConfigurator(
ConfigFile = "Log4Net.config", Watch = true)]
Declared as class variable
private static readonly ILog Log = LogManager.GetLogger(
MethodBase.GetCurrentMethod().DeclaringType);
In a method, called the Log like this
BasicConfigurator.Configure();
Log.Debug("Myjob");
Log.Error("newlkjasdf");
Log.Info("lkjlkjasdfasdf");

Try this appender :
<appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="log.txt" />
<appendToFile value="false" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="-1" />
<maximumFileSize value="10MB" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%-5p%d{yyyy-MM-dd hh:mm:ss} – %m%n" />
</layout>

log4net:ERROR Failed to find configuration section 'log4net'

I get this error when I try to configure my logger using:
log4net.Config.XmlConfigurator.Configure();
The app.config looks like this:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
<root>
<level value="ALL" />
<appender-ref ref="LogFileAppender" />
</root>
<appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender" >
<param name="File" value="C:\Logs\my-log-file.txt" />
<param name="AppendToFile" value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%date [%thread] %-5level %logger [%C{1}.%M] - %message%newline" />
</layout>
</appender>
</log4net>
</configuration>
I'm trying to write separate logs for each component of a system. I have one working for the main class but I get this error when trying to configure another one for a different class. What is the cause?
Thanks in adv!

I ended up using the following to configure my Add-In and RTD:
[Add-In]
log4net.Config.XmlConfigurator.Configure(
new FileInfo(AppDomain.CurrentDomain.BaseDirectory + "MyAdd-In.dll.config"));
[RTD]
log4net.Config.XmlConfigurator.Configure(
new FileInfo(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + "\\RtdServer.dll.config"));
Which then configured the separate logger for my RTD.
Hth