Having a window, or many in your dreams represents either one of two things. Depending on the state of the window.
If you’re looking through the window in your dream, it means that you either want something on the other side, or you’re just observing because of a certain feeling. It could vary in emotions from jealousy, approval, hatred etc. Depending on what you see on the other side, if it’s positive, then you either yearn for it, or you like it. If it’s negative it can associate with all the other negative emotions.
If you’re looking at a reflection in the window, it could mean that there should be a re-evaluation of yourself. You might see something wrong with yourself, or your conscious is telling you that something’s not right with the way you are presently, either emotionally or physically.
I’m not sure how related this dream is to windows but… I was dreaming I was on the outside of a window on the top floor of an apartment building. I was laying on the windowsill/ledge, but I could not get back into the apartment.
At this point I have become lucid within the dream. But this is not a typical lucid dream where I’m in control the dream in the sense that I know that I cannot be harmed because I’m aware that I’m dreaming.
On the contrary, I believe that if I fall off the windowsill I will die because I would be plummeting several floors to concrete. Realizing that there is nothing I can do (because I can’t jump or fall to the ground because I believe I will die and I can’t get back into the apartment.) I close my eyes within the dream and I just tell myself to wake up. And thankfully I do wake up.
It was one of my more frightening dreams because usually in dreams where I feel that I’m going to die I don’t have a choice in the matter so when I die I simply wake up and realize it’s just a dream. This dream I felt that I would actually die in real life if I fell.