dates.aspx

<label for="txtEffectiveDate">Date To Process</label>

<asp:TextBox ID="txtEffectiveDate" runat="server"
    CssClass="inputWide datePick hilite" />
<asp:RequiredFieldValidator ID="valEffDateNotEmpty" runat="server"
    ControlToValidate="txtEffectiveDate"
    ErrorMessage="Date to Process date is required"
    Display="none"
    ValidationGroup="Workflow"
    SetFocusOnError="true" />
<asp:CompareValidator ID="valEffDate" runat="server"
    ControlToValidate="txtEffectiveDate"
    Type="date" Operator="DataTypeCheck" ErrorMessage="Date To Process is not a valid date"
    Display="none" ValidationGroup="Workflow" />