A DLL is used in the code. And you need to add the log4net configuration in App. Config, and then it goes wrong, prompting "configuration system failed to initialize" Add the following code to Configation <configSections>
<sectiongroup name= "usersettings" type= "System.Configuration.UserSettingsGroup, System, version=4.0.0.0, Culture =neutral, publickeytoken=b77a5c561934e089 ">
<section name= "Http.Properties.Settings" type= "System.Configuration.ClientSettingsSection, System, version= 4.0.0.0, Culture=neutral, publickeytoken=b77a5c561934e089 "allowexedefinition=" Machinetolocaluser " Requirepermission= "false"/>
</sectionGroup>
<section name= "log4net" type= "log4net. Config.log4netconfigurationsectionhandler,log4net "/>
</configSections>
Add code in the configation tag of the app. config file to cause "configuration system failed to initialize"