div tag default?

I am very new to Dreamweaver so this may sound extremely dumb but when I first
started using it I would get pop up messages asking questions (providing
assistance). For example, when I would click the table icon, a window would
pop up asking if i wanted to add div tags. I believe this was creating a new
CSS rule rather than placing the table under an existing one. I checked the
box in the pop window to no longer ask me but now I wish it would. Does anyone
know how to turn it back on??

Thanks,