I recently bought a new Adapter since I broke the plug on the original one. I had chatted with a Dell tech support person and they recommended this adapter. However when I got it, and plugged the new adapter in, it's saying that it's plugged in and not charging. Also when I reboot my system, I get a message on start up that I'm using an unknown adapter. Is it still the wrong adapter even tho it clearly says it will work for my system?