Install Revit 2015 from your original media or an authorized download.

Copy the code back into the Revit activation screen and click Next to finish. Modern System Compatibility

This is typically found in your Autodesk Account under the "Products & Services" tray or on the physical media label. Step-by-Step Activation Process

To activate Revit 2015, you must first have the correct identification details based on your specific product package: