title: Validation fails when adding script manager
body: <p>I have a few controls on my master page for email subscription.</p>
  
  <p>Web-form works fine but doesn't trigger the validation in-case one doesn't enter email address.</p>
  
  <pre><code>&lt;asp:UpdatePanel ID="updSubscribe" runat="server" UpdateMode="Conditional"&gt;
      &lt;ContentTemplate&gt;
              &lt;asp:Panel ID="pnlSubscribe" runat="server" &gt;
                  &lt;asp:TextBox ID="txtEmail" CssClass="form-control form-subscribe-input" runat="server" placeholder="YOUR EMAIL"&gt;&lt;/asp:TextBox&gt;
                   &lt;asp:RequiredFieldValidator ID="rfvEmailSub"  runat="server" ErrorMessage="*" ControlToValidate="txtEmail" ValidationGroup="SubEmail" &gt;&lt;/asp:RequiredFieldValidator&gt;
                   &lt;asp:RegularExpressionValidator ID="revEmailSub" runat="server" ErrorMessage="*" ControlToValidate="txtEmail" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*" ValidationGroup="SubEmail" &gt;&lt;/asp:RegularExpressionValidator&gt;
                   &lt;span class="input-group-btn"&gt;
                      &lt;asp:Button ID="btnSubscribe" CssClass="btn btn-maroon" runat="server" ValidationGroup="SubEmail" Text="Subscribe" onclick="btnSubscribe_Click" /&gt;
                  &lt;/span&gt;
              &lt;/asp:Panel&gt; 
              &lt;asp:Panel ID="pnlSubscribeMSG" CssClass="pnlSubscribeMSG" runat="server" &gt;
                  &lt;asp:Label ID="lblSubscribeMSG" runat="server" Text=""&gt;
              &lt;/asp:Label&gt;
          &lt;/asp:Panel&gt;
      &lt;/ContentTemplate&gt;
  &lt;/asp:UpdatePanel&gt;
  </code></pre>
  
  <p>I am not sure what is wrong with the code.</p>
  
  <p><strong>Update</strong>:</p>
  
  <p>On further troubleshooting i noticed that same code works with validation on page with no masterpage.</p>
  
  <p>Not sure what is actually happening.</p>