Login tiga kali kesempatan

Buatlah form login seperti gambar di bawah ini :

login

Coding :

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Try
            Call Koneksi()
            CMD = New SqlCommand("select * from tbluser where nama_user='" & TextBox1.Text & "' and pwd_user='" & TextBox2.Text & "'", CONN)
            DR = CMD.ExecuteReader
            DR.Read()
            If Not DR.HasRows Then
                coba = coba + 1
                MsgBox("Kesempatan ke " & coba & " Salah")
                TextBox1.Clear()
                TextBox2.Clear()
                TextBox1.Focus()
                If coba = 3 Then
                    MsgBox("Kesempatan habis")
                    End
                End If
            Else
                Msgbox "Login sukses"
                    Me.Visible = False
                    MenuUtama.Show()
            End If
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub