Clear/Delete Cookies when user leave page.

<pre lang="vb">Protected Sub AutenicateUser(ByVal DomainName As String, ByVal UserName As String, ByVal Password As String)


        Dim adPath As String = ConfigurationManager.AppSettings("LDAP_ROOT")

        Dim adAuth As New UserAuthenticationValation.ActiveDirectorAuthentication(adPath)
        Try
            If True = adAuth.IsAuthenticated(DomainName, UserName, Password) Then
                Dim groups As String = adAuth.GetGroups(DomainName, UserName, Password)

                'Create the ticket, and add the groups.
                Dim isCookiePersistent As Boolean = chkPersist.Checked
                Dim authTicket As FormsAuthenticationTicket = New FormsAuthenticationTicket(1, _
                     txtUsername.Text, DateTime.Now, DateTime.Now.AddMinutes(60), isCookiePersistent, groups)

                'Encrypt the ticket.
                Dim encryptedTicket As String = FormsAuthentication.Encrypt(authTicket)

                'Create a cookie, and then add the encrypted ticket to the cookie as data.
                authCookie = New HttpCookie(FormsAuthentication.FormsCookieName, encryptedTicket)
                If (isCookiePersistent = True) Then
                    authCookie.Expires = authTicket.Expiration
                End If
                'Add the cookie to the outgoing cookies collection.
                Response.Cookies.Add(authCookie)

                Dim Subgroups As String() = groups.Split(New Char() {"|"c})
                Dim GroupName As String
                For Each GroupName In Subgroups
                    If GroupName = mstrValidateGroup Then
                        mbValidationFail = True
                        Exit For
                    End If
                Next
                'You can redirect now.
                If mbValidationFail = True Then
                    Session("User_id") = UserName
                    mstrUserID = UserName
                    Response.Redirect("Default.aspx")
                Else
                    lblError.Text = "At this time, you do not have access to this application." & "<BR> If you feel you have received this message in error, please contact the helpdesk @ 368-3375."

                End If
            Else
                lblError.Text = "Authentication did not succeed. Check user name and password."

            End If

        Catch ex As Exception
            lblError.Text = "Error authenticating. " & ex.Message
            lblError.Visible = True
        End Try

    End Sub



End Class