title: java.lang.ClassNotFoundException: javax.servlet.descriptor.JspConfigDescriptor
body: <p>I'm trying to build a JSF application, but I'm having this error:  </p>
  
  <pre><code>java.lang.ClassNotFoundException: javax.servlet.descriptor.JspConfigDescriptor
  java.lang.NoClassDefFoundError: javax/servlet/descriptor/JspConfigDescriptor
  </code></pre>
  
  <p>How is this caused and how can I solve it?</p>