C#

using System.IO.IsolatedStorage;

namespace Password
{
    public partial class MainPage : PhoneApplicationPage
    {
         IsolatedStorageSettings mySettings;

public void Settings()
    {
InitializeComponent();
//Initialize the settings
mySettings = IsolatedStorageSettings.ApplicationSettings;
// Display settings stored in the local storage for setUserName
if (mySettings.Contains("setUserName"))
txtUserName.Text = mySettings["setUserName"].ToString();
// Display settings stored in the local storage for setPassword
if (mySettings.Contains("setPassword"))
txtPassword.Password = mySettings["setPassword"].ToString();
}
        // Constructor
        public MainPage()
        {
            InitializeComponent();
        }

        private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
             if (txtUserName.Text != "" && txtPassword.Password != "")
{
if (txtPassword.Password == txtPasswordConfirm.Password)
{
//error here
if (mySettings.Contains("setUserName"))
//error here
{
mySettings["setUserName"] = txtUserName.Text;
}
else
mySettings.Add("setUserName", txtUserName.Text);
if (mySettings.Contains("setPassword"))
{
mySettings["setPassword"] = txtPassword.Password;
}
     else
mySettings.Add("setPassword", txtPassword.Password);
mySettings.Save();
MessageBox.Show("Settings Saved Successfully");
}
else
MessageBox.Show("Passwords are not matching");
        }
    }

        private void btnCancel_Click(object sender, RoutedEventArgs e)
        {
            NavigationService.GoBack();
        }
}}