private void pictureBox2_Click(object sender, EventArgs e)
{
frmManageChallen fm = new frmManageChallen();
fm.MdiParent = this.MdiParent;
fm.Show();
this.Close();
}
private void manageChallenToolStripMenuItem_Click(object sender, EventArgs e)
{
CloseAll();
frmManageChallen fmSale = new frmManageChallen();
fmSale.MdiParent = this;
fmSale.Show();
}