Hi makaish333,
I have created a sample which full fill your requirement
HTML
<asp:ScriptManager runat="server" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<div id="accordion">
<%--//////////////////////////////////////////////////////////////1//////////////////////////////////////////////////--%>
<h3>
1. Personal details
</h3>
<div>
<table class="border ">
<tr>
<td class="border italics">
Name
</td>
<td class="border italics">
<asp:TextBox ID="txtEmployeeName" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="border italics">
Position and role in firm
</td>
<td class="border italics">
<asp:TextBox ID="txtEmployeePosition" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="border italics">
Lotus Notes address
</td>
<td class="border italics">
<asp:TextBox ID="txtlnAdd" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td class="border italics">
Engagement Office
</td>
<td class="border italics">
<asp:TextBox ID="txtEngagementOffice" runat="server"></asp:TextBox>
</td>
</tr>
</table>
</div>
</div>
</ContentTemplate>
</asp:UpdatePanel>
<asp:Button ID="btnSubmit" Text="Submit" runat="server" />
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.9/jquery-ui.js" type="text/javascript"></script>
<link href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.9/themes/start/jquery-ui.css"
rel="stylesheet" type="text/css" />
<script type="text/javascript">
$(function () {
$("#accordion").accordion();
$('[id*=btnSubmit]').on('click', function () {
var table = $('[id*=accordion] TABLE');
var txtEmployeeName = table.find('[id*=txtEmployeeName]').val();
var txtEmployeePosition = table.find('[id*=txtEmployeePosition]').val();
var txtlnAdd = table.find('[id*=txtlnAdd]').val();
var txtEngagementOffice = table.find('[id*=txtEngagementOffice]').val();
var message = "";
if (txtEmployeeName == "") {
message += 'Please Enter EmployeeName' + '\n';
}
if (txtEmployeePosition == "") {
message += 'Please Enter EmployeePosition' + '\n';
}
if (txtlnAdd == "") {
message += 'Please Enter Address' + '\n';
}
if (txtEngagementOffice == "") {
message += 'Please Enter EngagementOffice';
}
if (message != "") {
alert(message);
}
});
});
var prm = Sys.WebForms.PageRequestManager.getInstance();
if (prm != null) {
prm.add_endRequest(function (sender, e) {
if (sender._postBackSettings.panelsToUpdate != null) {
$("#accordion").accordion();
}
});
};
</script>
ScreenShot
Hope this works for you