At that point you need to call microsoft support and explain the issue, they will ask for your key and you have to tell them the key and they will be able to tell you whether the key was used or if it is for another version of windows.
At that point you need to call microsoft support and explain the issue, they will ask for your key and you have to tell them the key and they will be able to tell you whether the key was used or if it is for another version of windows.