Laptop Keyboard Not Working

I have a year old Dell Inspiron N5030 laptop with Windows 7 and my hard-drive went bad. I purchased a new one, put the new one in, installed windows 7 and everything seemed to be working. I updated with windows updates, just finished and my keyboard and touchpad are no longer working. I did some searching online and one forum suggested the keyboard and touchpad cables came loose while putting in the new hard drive. I opened the laptop again, but no cables seem to be loose. Is this a hardware problem, software, windows update or what?