You can come across requirement when you need to disable hardware back button in Windows Phone 7.

If you want to disable hardware back button on Page1 then you need to override OnBackKeyPress method on Page1.

To disable you need to make CancelEventArgs value to cancel as given below,

If you want you can display a message to user when users try to navigate from back button. For your reference to disable back button code is given below.

using System.Windows;
using Microsoft.Phone.Controls;

namespace PhoneApp1
{
public partial class SecondPage : PhoneApplicationPage
{
public SecondPage()
{
InitializeComponent();
}

protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
//base.OnBackKeyPress(e);
MessageBox.Show("You can not use Hardware back button");

e.Cancel = true;
}

}
}

When run this code and try to navigate using back button, you will get a message and hardware back button will not work. You can have any other business requirement code in overridden OnBackKeyPress method as well. I hope this post is useful. Thanks for reading 

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