conuly

Do you know whether it's the top (the box up to the computer plug) or the bottom (cord)? Sometimes the bottom half of an adapter will die on its own from a small surge, and those are fortunately easily replaced.

Do you have a good surge protector? If you have one that's by APC or similar, it will come with basic coverage against the kind of damage you're running into. (If you don't have one...well...now would be a good time to change that!)