making a windows login system

[Bradley]

Hi,
Thanks for taking the interest in this post. I am trying to make a system Login using windows username and password I have got the code for the username already which is

Code:

Public Class form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        TextBox1.Text = System.Environment.UserName
    End Sub
End Class

What I need is how to confirm the windows password is correct

Example

If John had an account on a windows machine the username will display as John
And then he enters his password the same as he would in windows it then checks Johns permissions and displayers the appropriate form

2 forms

1 Administrator
2 standard users

The code to verify the users rights I have used the following

Code:

Public Class form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If My.User.IsInRole(ApplicationServices.BuiltInRole.Administrator) Then
            TextBox2.Text = "Administrator"
        Else
            TextBox2.Text = "Standard"
        End If
    End Sub
End Class

So the only missing peace to the puzzle is confirming the password

Any help is grateful or if you could give me guidance on where to get this information

Kind Regards

Bradley