HP KNOWS that their power adapters are shoddy. There are countless episodes of adapter failure, dongle failure and customer service nightmares. A search for replacement parts for my HP adapter returns 54$ as the lowest price for a OEM adapter, all the way up to 100+ from HP themselves. All of my friends with HP laptops have had the same issue with these power cords failing. Just a dongle is 65 dollars (OUTRAGEOUS!)
The fact of the matter is that HP is a fraudulent company who abuses its customers by providing shoddy products and even worse service. Tell all of your friends, technically-inclined or not, NOT to buy HP products. It'll save them a lot of money and a painful headache.