Keep getting disonnected from internet when using...

Question

My laptop instanteously disconnects from the internet if I plug in the laptop's power cord. If I remove the cord and run on the battery the internet connection returns...sometimes on its own...sometimes by running "repair". This happened one other time and lasted for about one day and then the problem went away on its own. In fact the first time I hadn't been able to determine what was causing the problem, i.e. power cord vs battery. This time the problem isn't going away and I have clearly found the problem. I have verified that this is happening in outlets throughout the home so it is not the outlet that is causing the problem.