Just keep calling man. You'll get a different person each time, and eventually one will activate it for you. If you were able to install windows with that CD Key, then clearly it's not just a typo. I reformat my computer all the time, and I usually do have to call customer service to get it activated. Though usually it goes without a hitch, sometimes I have to call back when the person says they won't activate it. Normally, all they ask you is why you re-activating the copy of windows, and if you have it installed on any other computers... Say no even if it's not true 😉, and they'll give you the activation number.