ok. I think that you are ok with the first part. in the second part, you have two approaches: in the 2nd dlg button write code that looks like this: void CDialog2::OnButton() { (CDialog1 pDlg*)=GetParent(); pDlg->m_ctlCheck1.SetCheck(FALSE); CDialog::OnOK(); } or after exiting the 2nd dialog set a flag and check it in the first diaog regards, Mohammad Gdeisat

i want some help to draw sin wave or somthing like that .. , and need some help about whitch tool can i ues .