Its very useful while click the checkbox the onclick funcation called jquery that hidden value used div will be open while checkbox checked. Uncheck the checkbox the div will be hid.

<input type="checkbox" id="ChangePassword" onclick = "DisplayChangePasswordField();"/>
 <input type="hidden" id="hidChangePassword" name="hidChangePassword" value="0" />
<div id="divchangepassword">
you can hid this div while clicking the checkbox.
</div>

$(document).ready(function () {
            $("#divchangepassword").hide();
        });
        function DisplayChangePasswordField() {
            var hideValue = $("#hidChangePassword").val();
            var newHideValue = 0;

            if (hideValue == 0) {
                newHideValue = 1;
            }
            else {
                newHideValue = 0;
            }
            if (newHideValue == 0) {
                $("#divchangepassword").hide();
            }
            else {
                $("#divchangepassword").show();
            }
            $("#hidChangePassword").val(newHideValue);
            return false;

        }    

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This error will happened when we will create new virtual directory in your project. your are miss some property settings. I have also some issue. I fixed easily.

Open IIS Manager

Select the Application pool drop down

Change the ASP.NET V4.0

Save the Properties

thats all.......

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