Help with child windows

Ok so I have this code below, I want to be able to hide the windows in the beginning then unhide them so that If a user chooses to enrypt it will unhide the encryption window. I'm lost at how to do it.

Does anyone know how to use child windows? How would I hide them when I create them, then make them visible?

It seems that with my code, they overlapp each other, but what I want to do is when the user makes a choice on the main window, change to the corresponding child window.

Try this, create the child window, then call the function ShowWindow and for the second argument pass SW_HIDE, then when you want it shown call ShowWindow again and pass SW_SHOW as the second argument. I never tried this with child windows but they are still windows so it should work, if not let me know.

Thanks a bunch, I actually thought about using it, but I guess I forgot or passed it up or something...