Comparevalidator on date type c#.net

how to solve this problem? I am having the same problem related to this link which was not answered. Can anyone help me.

 <telerik:RadDatePicker ID="DateTextBox" runat="server" Culture="en-GB" MinDate="1901-01-01"
                                TabIndex="4" FocusedDate="1991-01-01" MaxDate="2099-01-01">
                                <Calendar UseColumnHeadersAsSelectors="False" UseRowHeadersAsSelectors="False" ViewSelectorText="x">
                                </Calendar>
                                <DateInput DateFormat="dd/MM/yyyy" DisplayDateFormat="dd/MM/yyyy" TabIndex="4">
                                </DateInput>                                                                  
                            </telerik:RadDatePicker>

  <asp:CompareValidator ID="dateCompareValidator" runat="server" ControlToValidate="DateTextBox" ToolTip="The date to achieve the objective must be in the future"
                                    ErrorMessage="The date to achieve the objective must be in the future" Operator="GreaterThan" Type="Date"
                                    ValueToCompare='<%# DateTime.Now.ToString() %>'>*</asp:CompareValidator>

Intermittent error with CompareValidator - ValueToCompare property is ""

Solution

You have to set following properties of CompareValidator to validate date input.

ControlToValidate="controlId"
ErrorMessage="Error Message description"
Type="Date"
Operator="DataTypeCheck"

EDIT: Realized after the update of OP.

May be you have to set yyyy-MM-dd format.

 ValueToCompare='<%# DateTime.Now.ToString("yyyy-MM-dd") %>'>

Take a look at threads at telerik forum: