try to hide form instead of closing it, using
private void Playlist_FormClosed(object sender, FormClosedEventArgs e)
{
if (e.CloseReason == CloseReason.FormOwnerClosing) //if closed by aplication
{
this.Close();
}
if (e.CloseReason == CloseReason.UserClosing) //if closed by user
{
this.Hide();
}
}
but it's still close it, if User click Close.