<p>I recently started building a console version of a web application. I copied my custom sections from my web.config. to my app.config. When I go to get config information i get this error:</p>

<p>An error occurred creating the configuration section handler for x/y: Could not load type 'x' from assembly 'System.Configuration</p>

<p>The line that it is not liking is:</p>

<p>return ConfigurationManager.GetSection("X/Y") as Z;</p>

<p>Anyone run into something like this?</p>

<p>I was able to add </p>

<pre><code>&lt;add key="IsReadable" value="0"/&gt; 
</code></pre>

<p>in the appSettings and read it.</p>

<p>Addition:</p>

<p>I do actually have this defined about the custom section:</p>

<pre><code>  &lt;configSections&gt;
    &lt;sectionGroup name="x"&gt;
      &lt;section name="y" type="zzzzz"/&gt;
    &lt;/sectionGroup&gt;

  &lt;/configSections&gt;
</code></pre>

it sounds like your config-section handler is not defined
```
```
<configSection>
    <section
            name="YOUR_CLASS_NAME_HERE"
            type="YOUR.NAMESPACE.CLASSNAME, YOUR.NAMESPACE, Version=1.1.0.0, Culture=neutral, PublicKeyToken=PUBLIC_TOKEN_ID_FROM_ASSEMBLY"
            allowLocation="true"
            allowDefinition="Everywhere"
          />
</configSection>
```
```