0%
Because that is a placeholder or a cracked serial. No legitimate Autodesk software has ever used all zeros.
Assuming you have recovered your legitimate 555-xxxxxx serial number, here is the correct installation order for AutoCAD 2015 on Windows 10 or Windows 11. (Note: AutoCAD 2015 is not officially supported on Windows 11, but it does run with compatibility settings). autocad 2015 serial number product key