Hmmm, I'm not talking about the Form View/Design View button. When I open a form in design view I get a ruler across the top, and to the left of that a small grey box. Double-click on that and you'll get the Form's Properties.
Alternatively, go up to the taskbar where it has a white dropdown box and pick 'Form' from the list, then click the Properties button to view Properties.
HTH,
David R