title: The type or namespace name 'Net' does not exist in the namespace 'System'
body: <p>My C# file shows 3 different errors related to missing assembly references.</p>
  
  <p>I am using Xamarin studio and not sure where the references are located. The assembly browser?</p>
  
  <p>Here is where the errors are:</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Management;
  using System.Net;
  using System.IO;
  using System.Threading;
  using System.Diagnostics;
  using System.Collections.Specialized;
  using Microsoft.Win32;
  using System.Windows.Forms;
  </code></pre>
  
  <p>Errors:</p>
  
  <blockquote>
    <p>Error CS0234: The type or namespace name 'Net' does not exist in the namespace 'System' (are you missing an assembly reference?) (CS0234) (class)</p>
    
    <p>Error CS0234: The type or namespace name 'Specialized' does not exist in the namespace 'System.Collections' (are you missing an assembly reference?) (CS0234) (class)</p>
    
    <p>Error CS0234: The type or namespace name 'Windows' does not exist in the namespace 'System' (are you missing an assembly reference?) (CS0234) (class)</p>
  </blockquote>