Vb.net 2008 & aps.net & Login web control

Hi,

I have a page which i have added web login control. Based on the windows log on user name, the system picks the username and  display the name on the username textbox. When i try to put some default password on the password textbox . It picks ok but when i click on Login, it puts * on the password textbox. Is there a way i can avoid this so that i can put the default password and it goes through. Or is there a way i can remove validation on the password textbox.

WinLoggedinUser = System.Environment.UserName
        Login1.UserName = WinLoggedinUser
        Dim Password As TextBox = TryCast(Login1.FindControl("Password"), TextBox)
        If Password IsNot Nothing Then
            Password.Attributes("value") = "Password"
        End If

Please help am stuck