Rad combobox with compare validator

  <telerik:RadComboBox ID="ddlCourtName" runat="server"  ClientIDMode="Static" InitialValue="0" CssClass="uk-width-1-2" Filter="Contains" CheckBoxes="false" EnableCheckAllItemsCheckBox="false" Style="width: 50% !important;">

                                        <Localization CheckAllString="Select All" />

                                    </telerik:RadComboBox>

                                    <asp:CompareValidator runat="server" ValueToCompare="Select" Operator="NotEqual" ControlToValidate="ddlCourtName" ErrorMessage="required" CssClass="uk-width-1-4" ValidationGroup="StayDetailsValidationGroup" Display="Dynamic" SetFocusOnError="true" ForeColor="Red" />

ddlJudgementOrderIssuedBy.Items.Insert(0, new Telerik.Web.UI.RadComboBoxItem("Select", "0"));