title: Updatepanel not working with custom master page in sharepoint 2013
body: <p>I have created a sample update panel in visual webpart in sharepoint 2013. this code is working with default master page (seatle) but when i applies custom master page it would not work.</p>
  
  <pre><code>&lt;div&gt;
      &lt;br /&gt;
      &lt;asp:UpdatePanel ID="upSetSession" runat="server"&gt;
          &lt;ContentTemplate&gt;
              Current Time:
              &lt;asp:Label ID="lblTime" runat="server"&gt;&lt;/asp:Label&gt;&lt;br /&gt;
              &lt;asp:DropDownList ID="ddlMyList" runat="server" OnSelectedIndexChanged="ddlMyList_SelectedIndexChanged"
                  AutoPostBack="true"&gt;
                  &lt;asp:ListItem&gt;Select One&lt;/asp:ListItem&gt;
                  &lt;asp:ListItem&gt;Maybe&lt;/asp:ListItem&gt;
                  &lt;asp:ListItem&gt;Yes&lt;/asp:ListItem&gt;
              &lt;/asp:DropDownList&gt;
          &lt;/ContentTemplate&gt;
          &lt;Triggers&gt;
              &lt;asp:AsyncPostBackTrigger ControlID="ddlMyList" EventName="SelectedIndexChanged" /&gt;
          &lt;/Triggers&gt;
      &lt;/asp:UpdatePanel&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>and code behind is :</p>
  
  <pre><code>    protected void Page_Load(object sender, EventArgs e)
      {
  
      }
  
      protected void ddlMyList_SelectedIndexChanged(object sender, EventArgs e)
      {
          lblTime.Text = DateTime.Now.Second.ToString();
      }
  </code></pre>
  
  <p>I had already checked scriptmanager tag and webpart manager inside the sharepointform tag in custom master page.</p>