The version number matters. By the time V.5.7.7 rolled around, the software had become relatively polished compared to its earlier command-line predecessors. It featured a simple GUI with checkboxes for "Unlock," "Unlock Dashboard," and "Flash Firmware."

The main advantage of 5.7.7 over older versions was better support for newer (at the time) HiSilicon-based chipsets and a more reliable algorithm for calculating unlock codes without needing a server connection.

Huawei Modem Unlocker V.5.7.7 is a fascinating artifact from the era of 3G USB dongles. For a hobbyist with an old E173 sitting in a drawer, running it inside a Windows 7 virtual machine might get that modem working on a different carrier.