Control within a panel aren't working?

I have a small windows application that consists of 1 form. On this form are several panel controls that acts as a container for other controls. These panels are accessed based a menu selections from the Forms Menu Control. My problem is that when I select a certain option to display a certain panel, I can enter data in textboxes (as a result of entering data, data should be displayed) but nothing happens. I even set a breakpoint on the event that should fire...the KeyPress event for these textbox controls. Each time I access a panel, I disable and make invisble the current panel and then enable and make visible the one that I want but still unable to use the controls on the focused panel. What am I doing wrong?

Thanks,