hi, maybe you can check here. hope it helps. thanks
http://knowledge.autodesk.com/contactus/activation-registration
Remember : without the difficult times in your LIFE, you wouldn't be who you are today. Be grateful for the good and the bad. ANGER doesn't solve anything. It builds nothing, but it can destroy everything...
Please mark this response as "Accept as Solution" if it answers your question. Kudos gladly accepted.