Hello I think student version is allowed only for 3 years if you haven't finished 3 years then try to key in your serial number if still doesn't work go to Autodesk technical support website and login your issue. Thanks
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...
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