@dave r said:

Go to Window>Model Info>Components. Are the boxes for 'Hde' ticked? If so, untick them.

No, they were not. It was an operator error. All I needed to do was move the outline of the window shown on the baseplate to where I wanted it and the wall comes back.
Bill

@dave r said:

Go to Window>Model Info>Components. Are the boxes for 'Hde' ticked? If so, untick them.

The boxes were not ticked. The wall is on layer0 and the layers box always shows layer0 visible, but if any editing is done to the wall it becomes hidden. Through all this the layers box shows layer0 visible.
Bill

I've loaded Housebuilder and built a wall and added a window. When I click down to edit window, the wall gets hid. I can bring it back with unhide, but I'm not able to change it. I'm looking for more clues about what I'm doing wrong.
Thanks
Bill