core.dll, i cant resolve this problem

[beginner]

<?xml version="1.0"?>
<configuration>
<configSections>
<sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGrou p, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
<section name="maddox.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</sectionGroup>
</configSections>
<applicationSettings>
<maddox.Properties.Settings>
<setting name="nativeDLL" serializeAs="String">
<value>parts\core\steam_api.dll</value>
</setting>
</maddox.Properties.Settings>
</applicationSettings>
<runtime>
<gcConcurrent enabled="true" />
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<publisherPolicy apply="yes" />
<probing privatePath="parts/core;parts/bob" />
</assemblyBinding>
</runtime>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0,Profile=Client"/>
</startup>
</configuration>