My laptop is not finding any wireless networks

My Sony Vasio laptop is not finding any wireless networks. Usually it finds two in my area and mine which is set up to use it is a hot spot on my phone. I would like to mention that someone had used my computer and for some reason deleted cookies. I remember seeing a list of different cookies although I don't know what he did. I have tried back dating the computer and it still doesn't find any networks in the area.