I have this laptop running windows xp that when I plug in my external hard drive it will ding like it knows that I have plugged something in, but it will not see my external hard drive. I tried plugging in a pin drive and it acted the same. I plug this external hard drive into laptops & desktops all day every day and never have a problem. This is the first time I have not been able to connect to a computer. I just attempted to connect to my personal computer and it connected fine. What can be wrong with the laptop?