If you have old drawings created in AutoCAD 2013, they are fully compatible with AutoCAD 2024/2025. Here’s the smart upgrade path:
You cannot legally generate a new Activation Code without a valid serial. Your only option is to contact Autodesk support – but they will likely tell you that AutoCAD 2013 is no longer supported, and you must upgrade to a current version (e.g., AutoCAD 2025) via subscription. Autocad 2013 Activation Code Xforce