title: Error "An attempt to track an entity or complex type failed because the entity or complex type"
body: <p>I created an ASP.NET web application (to consume a WCF Data Service) and added a service reference to <a href="http://services.odata.org/Northwind/Northwind.svc" rel="nofollow">http://services.odata.org/Northwind/Northwind.svc</a>.  Create a web page (.aspx) and added a GridView and Button control.</p>
  
  <p>Wrote the following code:</p>
  
  <pre><code>protected void Button1_Click(object sender, EventArgs e)
  {
      var o = new NorthwindSvcRef.NorthwindEntities(new Uri("http://services.odata.org/Northwind/Northwind.svc"));
  
      //The following works fine
      //------------------------
      //var q = o.Customers.Where(c =&gt; c.City == "London").ToList();
      //GridView1.DataSource = q;
      //GridView1.DataBind();
  
  
      //Following does not work
      //-----------------------
      var q = o.Customers
         .Where(c =&gt; c.City == "London")
         .Select(c =&gt; c);
  
      DataServiceCollection&lt;Customer&gt; oCustomers = new DataServiceCollection&lt;Customer&gt;(q);
      GridView1.DataSource = oCustomers;
      GridView1.DataBind();
  }
  </code></pre>
  
  <p>Once I execute the above code, I am experiencing the following error:</p>
  
  <blockquote>
    <p>An attempt to track an entity or complex type failed because the
    entity or complex type 'NorthwindSvcRef.Customer' does not implement
    the INotifyPropertyChanged interface.</p>
  </blockquote>
  
  <p>Can anyone help me on this?</p>
  
  <p>Thanks in advance</p>