timer1.Enabled = false;
private void Form1_Load(object sender, EventArgs e)
{
timer1.Enabled = true;
}
private void button1_Click(object sender, EventArgs e)
{
timer1.Enabled = false;
var form2 = new Form2();
if (form2.ShowDialog() == DialogResult.OK)
{
timer1.Enabled = true;
}
}