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<asp:UpdatePanel ID="UpdatePanel5" runat="server">
                                                    <ContentTemplate>
              <asp:TextBox runat="server" ID="OldPassword" TextMode="Password"   AutoPostBack="true" class="txtinput" ontextchanged="OldPassword_TextChanged" ></asp:TextBox><br/>
                         
                            </ContentTemplate>
                            </asp:UpdatePanel>
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protected void Page_Load(object sender, EventArgs e)
    {
       
        if (!IsPostBack)
        {            
        }
        this.OldPassword.Attributes.Add("value", OldPassword.Text);
    }
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protected void OldPassword_TextChanged(object sender, EventArgs e)
    {
                 this.OldPassword.Text = this.OldPassword.Attributes["value"].ToSt