After installation, your Device Manager should show:

Universal Serial Bus devices └── Nokia BB5 ADL Loader (COM3)

: Required for service tools like Infinity BEST or OST LA to remove security codes or fix software hangs.

The is a small software package that allows your Windows operating system to communicate with your Nokia feature phone. Without this driver, your PC will either not recognize the phone at all or will detect it as an "unknown device," making data transfer and firmware updates impossible.