Even when running as a standalone executable, the software may still store registration and configuration data in the Windows Registry or local application folders, meaning it isn't "fully portable" in the sense of leaving no trace on a host PC. Using the Free Demo Version

If you require a free, non-expiring tool that does not need a registration key, is a popular open-source alternative available on GitHub . It provides similar Modbus Master functionality without the commercial licensing restrictions.

For Modscan64 or any software, it's recommended to support developers by purchasing legitimate copies. If you're looking for diagnostic tools for OBD-II systems, consider exploring both free and paid options that are officially supported and distributed to ensure you get a reliable and secure tool.