I can't stop this timer :

```
    private void startTimer_Click(object sender, EventArgs e)
    {
        AppTimer.Enabled = true;
    }

    private void AppTimer_Tick(object sender, EventArgs e)
    {
        if (BarreProgression.Value < BarreProgression.Maximum)
        {
            ...
            BarreProgression.Value = BarreProgression.Value + 1;
        }
        else if (BarreProgression.Value == BarreProgression.Maximum)
        {

            MessageBox.Show("Finished");
            //AppTimer.Stop();
            AppTimer.Enabled = false;  
        }
    }

```

I have an infinity number of message boxes!
Any ideas?